JP2005325150A - Ink composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink composition being excellent in stability, dryability after printing, and ink delivery and giving an image excellent in glossiness, water resistance, ozone resistance, light fastness and rubbing resistance. <P>SOLUTION: The ink composition comprises a microparticle dispersion prepared by dispersing microparticles containing an oil-soluble compound having an oxidation potential nobler than 1.0 V (vs. SCE) and an ultraviolet absorber and/or an antioxidant in an aqueous medium. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ink composition comprising an aqueous fine particle dispersion, and more particularly, to an ink composition suitable for ink jet recording, in which a robust recorded image is obtained and excellent in color reproducibility, glossiness and scratch resistance. .

  In recent years, with the spread of computers, ink jet printers are widely used for printing on paper, film, cloth and the like not only in offices but also at home. Oil-based, water-based, and solid inks are known as ink-jet inks. However, solvent-free and water-based inks have been demanded from the viewpoints of manufacturing, handling, odor, safety, etc. Is widely used.

Water-based inks that use water-soluble dyes include aqueous solutions of water-soluble dyes that are mainly classified as acid dyes, direct dyes, and some food dyes. Glycols, alkanolamines, and surface tension adjusters are used as humectants. For this purpose, a surfactant added with a thickener as necessary is used. Water-based inks using these water-soluble dyes are most commonly used because of their high reliability against clogging at the tip of a brush or printer, but they tend to bleed on recording paper (bleed), limit their intended use, and record Degradation has been forced. That is, it is difficult to say that a water-soluble dye that has just penetrated into a recording paper and has been dry-fixed is “dyed”, and has light resistance and oxidation resistance gas (SO _x , NO _x , ozone, etc.). It had the disadvantage of being bad.

  Accordingly, water-based inks using pigments and disperse dyes have been proposed for the purpose of solving the above problems (see, for example, Patent Documents 1 to 5). Although these water-based inks improve water resistance to a certain extent, they are not perfect, especially in the case of pigment inks, color development is inferior to dye inks, and the storage stability of the dispersion is poor, and clogging at the discharge port is likely to occur. It had such drawbacks. Further, when the disperse dye is used, it is equivalent to the water-soluble dye in terms of transparency and color density, but the image storage stability is not greatly improved as compared with the water-soluble dye.

  In addition, when recording paper (so-called photographic quality paper) provided with an ink receiving layer containing a porous inorganic pigment on the surface, which appeared due to the recent trend toward higher image quality in inkjet technology, the above pigments and disperse dyes can be used. It was found that the water-based ink used had poor penetrability and that the dyed pigment was easily peeled off from the surface when rubbed by hand.

  In addition, a method of encapsulating a dye in polyurethane or polyester dispersion particles has been proposed (for example, Patent Documents 6 to 10). However, the dispersions described in these publications have the disadvantage that it is difficult to obtain colored particles having excellent dispersion stability when the dye is encapsulated in a desired concentration. It was.

  On the other hand, Patent Document 11 proposes a method of encapsulating a dye mainly in a condensation polymer (such as polyurethane) having a dissociable group, and a high-boiling solvent (water-soluble or water-insoluble) may be present. Is described. However, only a very small amount of the water-insoluble hydrophobic high-boiling solvent is disclosed among the high-boiling solvents, and it is possible to solve the dye peeling that occurs when used in the above-mentioned photographic quality paper. It was not a thing.

  Also, in order to solve the problem that water-based inks using water-soluble dyes have low water resistance and light fastness, proposals for coloring water-dispersible resins with oil-soluble dyes or hydrophobic dyes have been made as inks for inkjet recording. Yes. As such an ink for ink jet recording, for example, an ink using emulsion polymer particles dyed with oil-soluble dyes or dispersed polymer particles has been proposed (see, for example, Patent Documents 12 to 18).

  However, the ink using the above polymerized particles is liable to cause aggregation and sedimentation between the particles and is inferior in ink stability. In addition, there is a drawback in the hue when printing, and there is a disadvantage that the printing density is low. Patent Documents 19 to 23 propose a method of encapsulating a dye in polyurethane or polyester dispersion particles. However, the dispersions described in these publications have the disadvantage that it is difficult to obtain colored particles having excellent dispersion stability when the dye is encapsulated in a desired concentration. It was.

  On the other hand, Patent Document 24 proposes a method in which a dye is mainly included in a condensation polymer (such as polyurethane) having a dissociable group, and a high-boiling solvent (water-soluble or water-insoluble) may be present. Is described. However, only a very small amount of the water-insoluble hydrophobic high-boiling solvent is disclosed among the high-boiling solvents, which solves the dye peeling that occurs when used for the above photographic image quality. It wasn't possible.

  Further, Patent Document 25 discloses a method for producing colored polymer fine particles by dissolving an acrylic polymer and an oil-soluble dye in an organic solvent and removing the organic solvent after dispersion. There was a problem in the quality when recording on the paper medium and the stability in continuous recording. Also, the stability with time of the dispersion was not sufficient.

As described above, various methods have been proposed in the past, but in water-based inks that are advantageous from the viewpoint of environmental sanitation and resource saving, the ejection stability is high, there is no paper dependency restriction, and the quality of the recorded image is high. At present, an ink composition that can obtain good color reproducibility, is excellent in color tone, and is excellent in fastness to light and water resistance has not yet been provided.
JP-A-56-157468 JP-A-4-18468 JP-A-8-183920 JP-A-10-110126 JP-A-10-195355 JP 58-45272 A JP-A-6-340825 JP 7-268254 A JP 7-268257 A JP 7-268260 A JP-A-11-286637 JP 55-139471 A JP 58-45272 A Japanese Patent Laid-Open No. 3-250069 JP-A-8-253720 JP-A-8-92513 JP-A-8-183920 JP 2001-11347 A JP 58-45272 A JP-A-6-340825 JP 7-268254 A JP 7-268257 A JP 7-268260 A JP-A-11-286637 JP-A-10-279873

This invention is made | formed in view of the above conventional trouble, and makes it a subject to achieve the following objectives. That is,
An object of the present invention is a water-based ink that is advantageous in terms of handling, odorlessness, safety, etc., and has high ejection stability, and light resistance when printed on an arbitrarily selected recording medium, particularly ozone resistance and resistance. An object of the present invention is to provide an ink composition which is excellent in rubbing property and can be recorded with high density and high image quality.

The inventors of the present invention can improve the quality of a recorded image by allowing an ultraviolet absorber and / or an antioxidant to be present in the vicinity of an oil-soluble compound, particularly an oil-soluble dye, contained in a fine particle dispersion contained in an ink composition. In particular, the present inventors have found that an effect is found in improving fastness to light and durability, and have come up with the present invention. The ink composition of the present invention is an ink composition in which a conventional ultraviolet absorber and / or antioxidant is added in a later step, or a light transmittance adjusting layer containing an ultraviolet absorber and / or an antioxidant on the recording medium side. This is different from the method of separately providing the above.
The above-mentioned problem is solved by the following means. That is,
<1> Contains a fine particle dispersion in which fine particles containing an oil-soluble compound having an oxidation potential nobler than 1.0 V (vs SCE) and an ultraviolet absorber and / or an antioxidant are contained in an aqueous medium. An ink composition characterized by the above.

<2> The ink composition according to <1>, wherein the oil-soluble compound is an oil-soluble dye.

<3> The ink composition according to <1> or <2>, wherein the fine particle dispersion further contains a hydrophobic polymer.

<4> The ink composition according to any one of <1> to <3>, wherein a long wave end of an absorption wavelength of the ultraviolet absorbent is 410 nm or less.

<5> The item <1>, wherein the ultraviolet absorber is at least one selected from the group consisting of benzophenones, benzotriazoles, oxalic anilides, cyanoacrylates, and triazines. <4> The ink composition according to any one of the above.

<6> The above <1> to <5>, wherein the antioxidant is at least one selected from the group consisting of phenols, phosphites, hindered amines, and thioethers The ink composition as described in 1. above.

<7> The ink composition according to any one of <1> to <6>, wherein the ink composition is for inkjet recording.

Furthermore, as the ink composition of the present invention, an embodiment in which the average particle diameter of fine particles containing an oil-soluble compound is 100 nm or less is particularly preferable.
In addition, as the ink composition of the present invention, an embodiment in which the fine particle dispersion containing an oil-soluble compound particularly contains at least one compound represented by the following general formula (WI) or (W-II). preferable.

一般式（Ｗ−Ｉ）において、Ｒ²⁰¹とＲ²⁰²はそれぞれ独立に炭素原子数が２〜２０の飽和炭化水素であり、ｍ₁は２〜４０である。

In the general formula (W-I), R ²⁰¹ and R ²⁰² are each independently a saturated hydrocarbon having 2 to 20 carbon atoms, and m ₁ is 2 to 40.

一般式（Ｗ−ＩＩ）において、Ｒ²⁰³とＲ²⁰⁴はそれぞれ独立に炭素原子数が４〜１０の飽和炭化水素であり、Ｒ²⁰³とＲ²⁰⁴の炭素原子数の合計は８〜１８であり、ｍ₂は３〜２０である。

In the general formula (W-II), R ²⁰³ and R ²⁰⁴ are each independently a saturated hydrocarbon having 4 to 10 carbon atoms, and the total number of carbon atoms of R ²⁰³ and R ²⁰⁴ is 8 to 18, m ₂ is 3 to 20.

  According to the present invention, it has handleability, odorlessness and safety, is suitable for water-based ink for writing, water-based printing ink, ink for information recording, etc., excellent in ejection stability and printability, and arbitrarily selected recording It is possible to provide an ink composition that is excellent in light resistance when printed on a medium, in particular, ozone resistance and scratch resistance, and can be recorded at a high density and high image quality.

The ink composition of the present invention comprises fine particles comprising an oil-soluble compound having an oxidation potential nobler than 1.0 V (vs SCE) and a fine particle containing an ultraviolet absorber and / or an antioxidant in an aqueous medium. It is characterized by containing a dispersion.
It is useful and preferable as an ink composition that the oil-soluble compound is an oil-soluble dye (pigment).
Further, the fine particle dispersion is preferably a fine particle dispersion containing a hydrophobic polymer in view of water resistance and fastness of a recorded image.
The long wavelength end of the absorption wavelength of the ultraviolet absorber is preferably 410 nm or less, particularly in terms of light resistance and ozone resistance.
In addition, as the ultraviolet absorber, at least one selected from the group consisting of benzophenones, benzotriazoles, oxalic anilides, cyanoacrylates, and triazines is used to further improve light fastness. This is preferable.
Furthermore, examples of the antioxidant include 3,5-di-t-butyl-4-hydroxy-benzylphosphonate-diethyl ester, triethylene glycol-bis (3- (3-t-butyl-5-methyl- 4-Hydroxyphenyl) propionate is preferred from the viewpoint of further improving image storage stability.
Hereafter, each element which comprises the ink composition of this invention is demonstrated in detail.

[Fine particle dispersion]
First, each component (oil-soluble compound, ultraviolet absorber, antioxidant, etc.) of the fine particle dispersion contained in the ink composition of the present invention will be described.

(Oil-soluble compounds)
The fine particles in the present invention contain an oil-soluble compound as an essential component. Here, the oil-soluble compound includes all water-insoluble compounds and is not particularly limited, and can be appropriately selected from known compounds according to the purpose within a range not impairing the effects of the present invention. Examples of such oil-soluble compounds include oil-soluble dyes, ultraviolet absorbers, antioxidants, anti-fading agents, liquid crystal compounds, fluorescent compounds, electron-donating colorless dyes, organic EL materials, and polymers thereof. Etc.

  The oil-soluble compound used in the present invention means a compound that is substantially insoluble in water. More specifically, it means that the solubility in water at 25 ° C. (the mass of the dye that can be dissolved in 100 g of water) is 1 g or less, preferably 0.5 g or less, more preferably 0.1 g or less. . Among these compounds, examples of the oil-soluble compound in the present invention include so-called water-insoluble pigments and oil-soluble dyes, and oil-soluble dyes (oil-soluble dyes) are particularly preferable.

  The oil-soluble dye in the present invention preferably has a melting point of 200 ° C. or lower, more preferably has a melting point of 150 ° C. or lower, and still more preferably has a melting point of 100 ° C. or lower. By using an oil-soluble dye having a low melting point, the precipitation of pigment crystals in the fine particle dispersion and the ink composition is suppressed, and the storage stability of the ink composition is improved. Moreover, an oil-soluble dye may be used individually by 1 type, and may use 2 or more types together. Moreover, in the range which does not impair the effect of this invention, colorants, such as another water-based dye and a disperse dye, may contain as needed.

  As the oil-soluble compound in the present invention, an oil-soluble compound having an oxidation potential nobler than 1.0 V (vs SCE) is used. The oxidation potential is more preferable as it is noble, preferably the oxidation potential is more noble than 1.1 V (vs SCE), more preferably noble than 1.15 V (vs SCE), especially 1.2 V (vs. Most preferred are those that are more noble than SCE).

  The value of the oxidation potential represents the ease of transfer of electrons from the sample to the electrode. The larger the value (the higher the oxidation potential), the less transfer of electrons from the sample to the electrode, in other words, less oxidation. Represent. In relation to the structure of the compound, the oxidation potential becomes more noble by introducing an electron withdrawing group, and the oxidation potential becomes lower by introducing an electron donating group.

  The value of the oxidation potential, which will be described in detail below, means the potential at which the compound is an anode in voltammetry and the electron of the compound is extracted, and is considered to approximately match the energy level of HOMO in the ground state of the compound. Yes.

  The inventors have studied the ozone fastness of the colored image. As a result, there is a correlation between the oxidation potential of the compound used in the colored image and the ozone fastness, and the oxidation potential value is higher than that of the saturated calomel electrode (SCE). It has been found that ozone fastness is improved by using noble compounds.

  The reason why the ozone fastness of the colored image is improved can be explained by the relationship between the HOMO (highest occupied orbit) and LUMO (lowest empty orbit) of the compound and ozone gas. That is, it is considered that the colorant is oxidized by the reaction of the colorant HOMO and the ozone gas LUMO, and as a result, the ozone fastness of the colored image is lowered. The reactivity with ozone gas may be lowered by lowering the HOMO.

  A person skilled in the art can easily measure the value of the oxidation potential (Eox). Regarding this method, for example, “New Instrumental Methods in Electrochemistry” by P. Delahay (1954 Interscience Publishers), AJ Bard et al. “Electrochemical Methods” (1980 John Wiley & Sons), Akira Fujishima et al. "(Gigakudo Publisher, 1984).

The measurement of the oxidation potential will be specifically described. The oxidation potential is 1 × 10 ⁻⁴ to 1 × 10 ⁻⁶ mol · dm ^{−3 in} a solvent such as dimethylformamide or acetonitrile containing a supporting electrolyte such as sodium perchlorate or tetrapropylammonium perchlorate. Dissolve and measure as a value for SCE (saturated calomel electrode) using cyclic voltammetry or direct current polarography. The supporting electrolyte and solvent to be used can be selected appropriately depending on the oxidation potential and solubility of the test sample. The supporting electrolytes and solvents that can be used are described in pages 101 to 118 of Akira Fujishima et al., “Electrochemical Measurement Method” (published by Gihodo Publishing Co., Ltd., 1984).

  The value of the oxidation potential may be deviated by several tens of mil volts due to the influence of the inter-liquid potential difference or the liquid resistance of the sample solution, but the potential measured by calibrating with a standard sample (for example, hydroquinone). The reproducibility of the value of can be guaranteed.

The oxidation potential in the present invention is in N, N-dimethylformamide containing 0.1 mol · dm ⁻³ of tetrapropylammonium perchlorate as a supporting electrolyte (the concentration of the compound is 1 × 10 ⁻³ mol · dm ⁻³ ). The SCE (saturated calomel electrode) is used as the reference electrode, the graphite electrode is used as the working electrode, and the platinum electrode is used as the counter electrode, and values measured by direct current polarography are used.

  The oil-soluble compound used in the present invention can have any structure as long as it satisfies the above oxidation potential. In particular, yellow dyes have no structural restrictions because they have noble oxidation potential (low HOMO). Hereinafter, the structure of the oil-soluble compound necessary for satisfying the oxidation potential will be described in detail.

  In the present invention, in order to lower the reactivity with ozone as an electrophile, it is desirable to introduce an electron withdrawing group into the dye skeleton to make the oxidation potential more noble. Therefore, using Hammett's substituent constant σp value, which is a measure of the electron withdrawing property and electron donating property of the substituent, the σp value is as in nitro, cyano, sulfinyl, sulfonyl, and sulfamoyl groups. It can be said that the oxidation potential can be made more noble by introducing a large substituent.

  Hammett's substituent constant σp value will be described briefly. Hammett's rule is a method described in 1935 by L. E. in order to quantitatively discuss the effect of substituents on the reaction or equilibrium of benzene derivatives. P. A rule of thumb proposed by Hammett, which is widely accepted today. Substituent constants determined by Hammett's rule include a σp value and a σm value, and these values can be found in many general books. A. Dean, “Lange's Handbook of Chemistry”, 12th edition, 1979 (Mc Graw-Hill) and “Chemicals” special edition, 122, 96-103, 1979 (Nankodo).

  In addition to the above-described substituents, the oxidation potential can be made noble as the number of atoms having high electronegativity generally increases as the constituent atoms of the chromophore. Therefore, for example, when an unsaturated heterocycle is used as a constituent of a chromophore rather than an aryl group, the oxidation potential can be made noble. Examples of the heteroatom having a high electronegativity include a nitrogen atom, an oxygen atom, and a sulfur atom, and a nitrogen atom is particularly preferable.

  Accordingly, the oil-soluble compounds used in the present invention are preferably those in which the chromophore is composed of heteroatoms, those containing unsaturated heterocycles, and those containing electron-withdrawing groups. Preferred chromophores composed of heteroatoms include azo dyes, azomethine dyes, phthalocyanine dyes and the like, with azo dyes being particularly preferred. As the unsaturated heterocycle, a 5- or 6-membered unsaturated heterocycle is preferable, and a thiophene ring, furan ring, pyrrole ring, thiazole ring, oxazole ring, imidazole ring, isothiazole ring, isoxazole ring, pyrazole ring, thiadiazole ring. And oxadiazole ring, triazole ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring and the like. The unsaturated heterocycle may form a condensed ring with a hydrocarbon ring or a heterocycle. In the case of a nitrogen-containing heterocycle, the nitrogen atom may be quaternized. Further, with respect to the heterocycle that can be tautomeric, even when only one tautomer is described, other tautomers are also included. Of these, preferred are a thiazole ring, an isothiazole ring, a pyrazole ring, a thiadiazole ring, a pyridine ring, a pyrimidine ring, and a pyrazine ring. Most preferred are an isothiazole ring, a pyrazole ring, a 1,2,4-thiadiazole ring, a 1,3,4-thiadiazole ring, and a pyridine ring.

  As a preferable electron-withdrawing substituent, a substituent having a Hammett's σp value of 0.4 or more is preferable, a substituent of 0.45 or more is more preferable, and a substituent of 0.50 or more is most preferable. Further, when a plurality of electron-withdrawing groups are present as substituents on the chromophore, the sum of the σp values of the substituents is preferably 0.50 or more, more preferably 0.60 or more, and 0.70 The above is most preferable. Specific examples of the electron-withdrawing group having σp of 0.40 or more are described in J. A. Dean, “Lange's Handbook of Chemistry”, 12th edition, 1979 (Mc Graw-Hill) and “Chemicals” special edition, 122, 96-103, 1979 (Nankodo) I can do it.

As the structure of the yellow dye as the oil-soluble compound, it is preferable to use a compound represented by the following general formula (I).
Het (A) -N = N-Het (B) ..... General formula (I)
In general formula (I), Het (A) and Het (B) each independently represent a 5- or 6-membered unsaturated heterocycle having a substituent. Examples of unsaturated heterocycles represented by Het (A) and Het (B) include thiophene ring, furan ring, pyrrole ring, thiazole ring, oxazole ring, imidazole ring, isothiazole ring, isoxazole ring, pyrazole ring, Examples include a thiadiazole ring, an oxadiazole ring, a triazole ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, and a pyrazine ring. These unsaturated heterocycles may further have a substituent. The substituents on the unsaturated heterocycle may be bonded to each other to form a condensed ring with a hydrocarbon ring or an unsaturated heterocycle, and may further have a substituent on the condensed ring. In the case of a nitrogen-containing unsaturated heterocycle, the nitrogen atom may be quaternized. In addition, regarding unsaturated heterocycles that can be tautomeric, even when only one tautomer is described, other tautomers are also included.

  The heterocyclic ring represented by Het (A) and Het (B) is preferably a thiazole ring, isothiazole ring, pyrazole ring, thiadiazole ring, pyridine ring or pyrazine ring. More preferred are an isothiazole ring, a pyrazole ring, a thiadiazole ring, and a pyridine ring. Most preferred are a pyrazole ring, a 1,2,4-thiadiazole ring, and a pyridine ring.

  Het (A) and Het (B) may have a substituent. Substituents include halogen atoms, alkyl groups (including cycloalkyl groups), alkenyl groups (including cycloalkenyl groups), alkynyl groups, aryl groups, heterocyclic groups, cyano groups, hydroxyl groups, nitro groups, carboxyl groups, Alkoxy group, aryloxy group, silyloxy group, heterocyclic oxy group, acyloxy group, carbamoyloxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy, amino group (including anilino group), acylamino group, aminocarbonylamino group, alkoxy Carbonylamino group, aryloxycarbonylamino group, sulfamoylamino group, alkyl and arylsulfonylamino group, mercapto group, alkylthio group, arylthio group, heterocyclic thio group, sulfamoyl group, sulfo group, alkyl and Arylsulfinyl groups, alkyl and arylsulfonyl groups, acyl groups, aryloxycarbonyl groups, alkoxycarbonyl groups, carbamoyl groups, aryl and heterocyclic azo groups, imide groups, phosphino groups, phosphono groups, phosphinyl groups, phosphinyloxy groups, Examples include a phosphinylamino group and a silyl group. Among these, halogen atom, heterocyclic group, cyano group, nitro group, carboxyl group, acyloxy group, carbamoyloxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy, sulfamoyl group, sulfo group, alkyl and arylsulfinyl group, alkyl and Substituents such as arylsulfonyl group, acyl group, aryloxycarbonyl group, alkoxycarbonyl group, carbamoyl group, imide group, phosphoryl group, phosphono group, phosphinoyl group, phosphonyl group, phosphinoyloxy group, phosphinoylamino group Among them, an electron withdrawing group is preferable, and a substituent having σp of 0.40 or more is particularly preferable. Substituents with σp of 0.40 or more include cyano group, nitro group, carboxyl group, sulfamoyl group, alkyl and arylsulfinyl group, alkyl and arylsulfonyl group, acyl group, aryloxycarbonyl group, alkoxycarbonyl group, carbamoyl group , Imide groups, phosphono groups, phosphoryl groups, etc., alkyl groups substituted with electron-withdrawing groups (trihalomethyl groups, perfluoroalkyl groups, dicyanomethyl groups, iminomethyl groups, etc.), alkenyl groups substituted with electron-withdrawing groups (Tricyanovinyl group, etc.) Quaternary salt substituents (sulfonium group, ammonium group, phosphonium group) can also be mentioned. Among the above functional groups, those having a hydrogen atom may be substituted with the above groups by removing this. Examples of such substituent include alkylcarbonylaminosulfonyl group, arylcarbonylaminosulfonyl group, alkylsulfonylaminocarbonyl group, arylsulfonylaminocarbonyl group and the like. Moreover, when the substituents on the heterocycle are bonded to each other, a heterocycle and a condensed ring may be formed, and a substituent may be further provided on the condensed ring.

  As a preferable structure of the magenta dye, a compound represented by the following general formula (M-I) is preferably used.

In general formula (M-I), A represents a residue of a 5-membered heterocyclic diazo component A-NH ₂ . B ¹ and B ² each represent —CR ¹ ═ and —CR ² ═, or either one represents a nitrogen atom and the other represents —CR ¹ ═ or —CR ² ═. R ⁵ and R ⁶ are each independently a hydrogen atom, aliphatic group, aromatic group, heterocyclic group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, alkyl or arylsulfonyl group, or sulfamoyl group. Each group may further have a substituent.

G, R ¹ and R ² are each independently a hydrogen atom, halogen atom, aliphatic group, aromatic group, heterocyclic group, cyano group, carboxyl group, carbamoyl group, alkoxycarbonyl group, aryloxycarbonyl group, complex Ring oxycarbonyl group, acyl group, hydroxy group, alkoxy group, aryloxy group, heterocyclic oxy group, silyloxy group, acyloxy group, carbamoyloxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, amino group (heterocyclic amino Group, anilino group), acylamino group, ureido group, sulfamoylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, alkyl or arylsulfonylamino group, heterocyclic sulfonylamino group, nitro group, alkyl or arylthio Base Represents an alkyl or arylsulfonyl group, a heterocyclic sulfonyl group, an alkyl or arylsulfinyl group, a heterocyclic sulfinyl group, a sulfamoyl group, a sulfo group, or a heterocyclic thio group, and each group may be further substituted. R ¹ and R ⁵ , or R ⁵ and R ⁶ may combine to form a 5- or 6-membered ring.

In the general formula (M-I), A represents a residue of a 5-membered heterocyclic diazo component A-NH _2. Examples of heteroatoms for heterocycles include N, O, and S. A nitrogen-containing 5-membered heterocyclic ring is preferable, and an aliphatic ring, an aromatic ring or another heterocyclic ring may be condensed to the heterocyclic ring. Examples of preferred heterocyclic rings for A include pyrazole ring, imidazole ring, thiazole ring, isothiazole ring, thiadiazole ring, benzothiazole ring, benzoxazole ring, and benzoisothiazole ring. Each heterocyclic group may further have a substituent. Of these, pyrazole rings, imidazole rings, isothiazole rings, thiadiazole rings, and benzothiazole rings represented by the following general formulas (a) to (f) are preferable.

In the general formulas (a) to (f), R ⁷ to R ²⁰ represent the same substituents as those described for G, R ¹ and R ² . Of the general formulas (a) to (f), preferred are a pyrazole ring represented by the general formula (a) and an isothiazole ring represented by the general formula (b), and most preferred is the general formula. It is a pyrazole ring represented by (a).

In the general formula (M-I), B ¹ and B ² each represent —CR ¹ ═ and —CR ² ═, or either one is a nitrogen atom and the other is —CR ¹ ═ or —CR ² ═. represents but each -CR ¹ =, - represents a CR ² = is more preferable.

R ⁵ and R ⁶ are each independently a hydrogen atom, aliphatic group, aromatic group, heterocyclic group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, alkyl or arylsulfonyl group, sulfamoyl group. Each group may further have a substituent. Preferable substituents represented by R ⁵ and R ⁶ include a hydrogen atom, aliphatic group, aromatic group, heterocyclic group, acyl group, alkyl or arylsulfonyl group. More preferably, they are a hydrogen atom, an aromatic group, a heterocyclic group, an acyl group, an alkyl or arylsulfonyl group. Most preferably, they are a hydrogen atom, an aryl group, and a heterocyclic group. Each group may further have a substituent. However, R ⁵ and R ⁶ are not simultaneously hydrogen atoms.

G, R ¹ and R ² are each independently a hydrogen atom, halogen atom, aliphatic group, aromatic group, heterocyclic group, cyano group, carboxyl group, carbamoyl group, alkoxycarbonyl group, aryloxycarbonyl group, Heterocyclic oxycarbonyl group, acyl group, hydroxy group, alkoxy group, aryloxy group, heterocyclic oxy group, silyloxy group, acyloxy group, carbamoyloxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, amino group (anilino group) A heterocyclic amino group), acylamino group, ureido group, sulfamoylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, alkyl or arylsulfonylamino group, heterocyclic sulfonylamino group, nitro group, alkyl and An arylthio group, It represents a heterocyclic thio group, an alkyl and arylsulfonyl group, a heterocyclic sulfonyl group, an alkyl and arylsulfinyl group, a heterocyclic sulfinyl group, a sulfamoyl group, or a sulfo group, and each group may be further substituted.

  Examples of the substituent represented by G include a hydrogen atom, halogen atom, aliphatic group, aromatic group, hydroxy group, alkoxy group, aryloxy group, acyloxy group, heterocyclic oxy group, amino group (anilino group, heterocyclic ring). (Including amino groups), acylamino groups, ureido groups, sulfamoylamino groups, alkoxycarbonylamino groups, aryloxycarbonylamino groups, alkyl and arylthio groups, or heterocyclic thio groups, more preferably hydrogen atoms or halogen atoms. , An alkyl group, a hydroxy group, an alkoxy group, an aryloxy group, an acyloxy group, an amino group (including an anilino group and a heterocyclic amino group) or an acylamino group, among which a hydrogen atom, an anilino group and an acylamino group are most preferable. Each group may further have a substituent.

Preferable substituents represented by R ¹ and R ² include a hydrogen atom, an alkyl group, a halogen atom, an alkoxycarbonyl group, a carboxyl group, a carbamoyl group, a hydroxy group, an alkoxy group, and a cyano group. Each group may further have a substituent. R ¹ and R ⁵ , or R ⁵ and R ⁶ may combine to form a 5- or 6-membered ring.

Examples of the substituent in the case where each of the substituents represented by A, R ¹ , R ² , R ⁵ , R ⁶ , and G further has a substituent include the substituents exemplified for G, R ¹ , and R ² above. be able to.

In the present specification, an aliphatic group means an alkyl group, a substituted alkyl group, an alkenyl group, a substituted alkenyl group, an alkynyl group, a substituted alkynyl group, an aralkyl group, and a substituted aralkyl group. The aliphatic group may have a branch and may form a ring. The number of carbon atoms in the aliphatic group is preferably 1-20, and more preferably 1-16. The aryl moiety of the aralkyl group and substituted aralkyl group is preferably phenyl or naphthyl, and particularly preferably phenyl.
Examples of aliphatic groups include methyl, ethyl, butyl, isopropyl, t-butyl, hydroxyethyl, methoxyethyl, cyanoethyl, trifluoromethyl, 3-sulfopropyl, 4-sulfobutyl Group, cyclohexyl group, benzyl group, 2-phenethyl group, vinyl group, and allyl group.

  In this specification, an aromatic group means an aryl group and a substituted aryl group. The aryl group is preferably phenyl or naphthyl, particularly preferably phenyl. The number of carbon atoms in the aromatic group is preferably 6 to 20, and more preferably 6 to 16. Examples of the aromatic group include phenyl, p-tolyl, p-methoxyphenyl, o-chlorophenyl and m- (3-sulfopropylamino) phenyl.

  The heterocyclic group includes a heterocyclic group having a substituent and an unsubstituted heterocyclic group. The heterocyclic ring may be condensed with an aliphatic ring, an aromatic ring or another heterocyclic ring. The heterocyclic group is preferably a 5-membered or 6-membered heterocyclic group. Examples of the substituent include aliphatic groups, halogen atoms, alkyl and arylsulfonyl groups, acyl groups, acylamino groups, sulfamoyl groups, carbamoyl groups, ionic hydrophilic groups and the like. Examples of the heterocyclic group include 2-pyridyl group, 2-thienyl group, 2-thiazolyl group, 2-benzothiazolyl group, 2-benzoxazolyl group and 2-furyl group.

  The alkyl and arylsulfonyl groups include substituted alkyl and arylsulfonyl groups, unsubstituted alkyl and arylsulfonyl groups. Examples of the alkyl and arylsulfonyl groups include a methylsulfonyl group and a phenylsulfonyl group, respectively.

  Alkyl and arylsulfinyl groups include substituted alkyl and arylsulfinyl groups, unsubstituted alkyl and arylsulfinyl groups. Examples of the alkyl and arylsulfinyl groups include a methylsulfinyl group and a phenylsulfinyl group, respectively.

  The acyl group includes an acyl group having a substituent and an unsubstituted acyl group. The acyl group is preferably an acyl group having 1 to 20 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the acyl group include an acetyl group and a benzoyl group.

  Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.

  The amino group includes an amino group substituted with an alkyl group, an aryl group or a heterocyclic group, and the alkyl group, the aryl group and the heterocyclic group may further have a substituent. As the alkylamino group, an alkylamino group having 1 to 20 carbon atoms is preferable. Examples of the substituent include an ionic hydrophilic group. Examples of the alkylamino group include a methylamino group and a diethylamino group.

  The arylamino group includes an arylamino group having a substituent and an unsubstituted arylamino group. The arylamino group is preferably an arylamino group having 6 to 20 carbon atoms. Examples of the substituent include a halogen atom and an ionic hydrophilic group. Examples of the arylamino group include a phenylamino group and a 2-chlorophenylamino group.

  The heterocyclic amino group includes a heterocyclic amino group having a substituent and an unsubstituted heterocyclic amino group. As the heterocyclic amino group, a heterocyclic amino group having 2 to 20 carbon atoms is preferable. Examples of the substituent include an alkyl group, a halogen atom, and an ionic hydrophilic group.

  The alkoxy group includes an alkoxy group having a substituent and an unsubstituted alkoxy group. As said alkoxy group, a C1-C20 alkoxy group is preferable. Examples of the substituent include an alkoxy group, a hydroxyl group, and an ionic hydrophilic group. Examples of the alkoxy group include a methoxy group, an ethoxy group, an isopropoxy group, a methoxyethoxy group, a hydroxyethoxy group, and a 3-carboxypropoxy group.

  The aryloxy group includes an aryloxy group having a substituent and an unsubstituted aryloxy group. The aryloxy group is preferably an aryloxy group having 6 to 20 carbon atoms. Examples of the substituent include an alkoxy group and an ionic hydrophilic group. Examples of the aryloxy group include a phenoxy group, a p-methoxyphenoxy group, and an o-methoxyphenoxy group.

  The silyloxy group is preferably a silyloxy group substituted with an aliphatic group or aromatic group having 1 to 20 carbon atoms. Examples of the silyloxy group include trimethylsilyloxy and diphenylmethylsilyloxy.

  The heterocyclic oxy group includes a heterocyclic oxy group having a substituent and an unsubstituted heterocyclic oxy group. As the heterocyclic oxy group, a heterocyclic oxy group having 2 to 20 carbon atoms is preferable. Examples of the substituent include an alkyl group, an alkoxy group, and an ionic hydrophilic group. Examples of the heterocyclic oxy group include a 3-pyridyloxy group and a 3-thienyloxy group.

  The alkoxycarbonyloxy group includes an alkoxycarbonyloxy group having a substituent and an unsubstituted alkoxycarbonyloxy group. As the alkoxycarbonyloxy group, an alkoxycarbonyloxy group having 2 to 20 carbon atoms is preferable. Examples of the alkoxycarbonyloxy group include a methoxycarbonyloxy group and an isopropoxycarbonyloxy group.

  The aryloxycarbonyloxy group includes an aryloxycarbonyloxy group having a substituent and an unsubstituted aryloxycarbonyloxy group. The aryloxycarbonyloxy group is preferably an aryloxycarbonyloxy group having 7 to 20 carbon atoms. Examples of the aryloxycarbonyloxy group include a phenoxycarbonyloxy group.

  The acylamino group includes an acylamino group having a substituent and an unsubstituted acylamino group. The acylamino group is preferably an acylamino group having 2 to 20 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the acylamino group include an acetylamino group, a propionylamino group, a benzoylamino group, an N-phenylacetylamino group, and a 3,5-disulfobenzoylamino group.

  The ureido group includes a ureido group having a substituent and an unsubstituted ureido group. The ureido group is preferably a ureido group having 1 to 20 carbon atoms. Examples of the substituent include an alkyl group and an aryl group. Examples of the ureido group include a 3-methylureido group, a 3,3-dimethylureido group, and a 3-phenylureido group.

  The sulfamoylamino group includes a sulfamoylamino group having a substituent and an unsubstituted sulfamoylamino group. Examples of the substituent include an alkyl group. Examples of the sulfamoylamino group include an N, N-dipropylsulfamoylamino group.

  The alkoxycarbonylamino group includes an alkoxycarbonylamino group having a substituent and an unsubstituted alkoxycarbonylamino group. Examples of the substituent in which an alkoxycarbonylamino group having 2 to 20 carbon atoms is preferable as the alkoxycarbonylamino group include an ionic hydrophilic group. Examples of the alkoxycarbonylamino group include an ethoxycarbonylamino group.

  The alkyl and arylsulfonylamino groups include substituted alkyl and arylsulfonylamino groups, and unsubstituted alkyl and arylsulfonylamino groups. As the sulfonylamino group, a sulfonylamino group having 1 to 20 carbon atoms is preferable. Examples of the substituent include an ionic hydrophilic group. Examples of the sulfonylamino group include a methylsulfonylamino group, an N-phenyl-methylsulfonylamino group, a phenylsulfonylamino group, and a 3-carboxyphenylsulfonylamino group.

  The carbamoyl group includes a carbamoyl group having a substituent and an unsubstituted carbamoyl group. Examples of the substituent include an alkyl group. Examples of the carbamoyl group include a methylcarbamoyl group and a dimethylcarbamoyl group.

  The sulfamoyl group includes a sulfamoyl group having a substituent and an unsubstituted sulfamoyl group. Examples of the substituent include an alkyl group. Examples of the sulfamoyl group include a dimethylsulfamoyl group and a di- (2-hydroxyethyl) sulfamoyl group.

  The alkoxycarbonyl group includes an alkoxycarbonyl group having a substituent and an unsubstituted alkoxycarbonyl group. As the alkoxycarbonyl group, an alkoxycarbonyl group having 2 to 20 carbon atoms is preferable. Examples of the substituent include an ionic hydrophilic group. Examples of the alkoxycarbonyl group include a methoxycarbonyl group and an ethoxycarbonyl group.

  The acyloxy group includes an acyloxy group having a substituent and an unsubstituted acyloxy group. As the acyloxy group, an acyloxy group having 1 to 20 carbon atoms is preferable. Examples of the substituent include an ionic hydrophilic group. Examples of the acyloxy group include an acetoxy group and a benzoyloxy group.

  The carbamoyloxy group includes a carbamoyloxy group having a substituent and an unsubstituted carbamoyloxy group. Examples of the substituent include an alkyl group. Examples of the carbamoyloxy group include an N-methylcarbamoyloxy group.

  The aryloxycarbonyl group includes an aryloxycarbonyl group having a substituent and an unsubstituted aryloxycarbonyl group. As the aryloxycarbonyl group, an aryloxycarbonyl group having 7 to 20 carbon atoms is preferable. Examples of the substituent include an ionic hydrophilic group. Examples of the aryloxycarbonyl group include a phenoxycarbonyl group.

  The aryloxycarbonylamino group includes an aryloxycarbonylamino group having a substituent and an unsubstituted aryloxycarbonylamino group. The aryloxycarbonylamino group is preferably an aryloxycarbonylamino group having 7 to 20 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the aryloxycarbonylamino group include a phenoxycarbonylamino group.

  The alkyl, aryl and heterocyclic thio groups include substituted alkyl, aryl and heterocyclic thio groups and unsubstituted alkyl, aryl and heterocyclic thio groups. Alkyl, aryl and heterocyclic thio groups are preferably those having 1 to 20 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the alkyl, aryl and heterocyclic thio groups include a methylthio group, a phenylthio group, and a 2-pyridylthio group.

  The heterocyclic oxycarbonyl group includes a heterocyclic oxycarbonyl group having a substituent and an unsubstituted heterocyclic oxycarbonyl group. The heterocyclic oxycarbonyl group is preferably a heterocyclic oxycarbonyl group having 2 to 20 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the heterocyclic oxycarbonyl group include a 2-pyridyloxycarbonyl group.

  The heterocyclic sulfonylamino group includes a substituted heterocyclic sulfonylamino group and an unsubstituted heterocyclic sulfonylamino group. The heterocyclic sulfonylamino group is preferably a heterocyclic sulfonylamino group having 1 to 12 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the heterocyclic sulfonylamino group include a 2-thiophenesulfonylamino group and a 3-pyridinesulfonylamino group.

  The heterocyclic sulfonyl group includes a heterocyclic sulfonyl group having a substituent and an unsubstituted heterocyclic sulfonyl group. The heterocyclic sulfonyl group is preferably a heterocyclic sulfonyl group having 1 to 20 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the heterocyclic sulfonyl group include a 2-thiophenesulfonyl group and a 3-pyridinesulfonyl group.

  The heterocyclic sulfinyl group includes a heterocyclic sulfinyl group having a substituent and an unsubstituted heterocyclic sulfinyl group. The heterocyclic sulfinyl group is preferably a heterocyclic sulfinyl group having 1 to 20 carbon atoms. Examples of the substituent include an ionic hydrophilic group. Examples of the heterocyclic sulfinyl group include a 4-pyridinesulfinyl group.

  In the present invention, the compound represented by the general formula (M-I) is preferably a compound represented by the following general formula (M-II).

In General Formula (M-II), Z ¹ represents an electron-withdrawing group having a Hammett's substituent constant σp value of 0.20 or more. Z ¹ is preferably an electron-withdrawing group having a σp value of 0.30 or more, more preferably 0.45 or more, and particularly preferably an electron-withdrawing group of 0.60 or more. It is desirable not to exceed zero. Specific examples of the preferred substituent include an electron-withdrawing substituent described later. Among them, an acyl group having 2 to 20 carbon atoms, an alkyloxycarbonyl group having 2 to 20 carbon atoms, a nitro group, a cyano group, An alkylsulfonyl group having 1 to 20 carbon atoms, an arylsulfonyl group having 6 to 20 carbon atoms, a carbamoyl group having 1 to 20 carbon atoms, and a halogenated alkyl group having 1 to 20 carbon atoms are preferable. Particularly preferred are a cyano group, an alkylsulfonyl group having 1 to 20 carbon atoms, and an arylsulfonyl group having 6 to 20 carbon atoms, and most preferred is a cyano group.

R ¹ , R ² , R ⁵ and R ⁶ have the same meanings as in the general formula (MI).
R ³ and R ⁴ are each independently a hydrogen atom, aliphatic group, aromatic group, heterocyclic group, acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group, alkyl and arylsulfonyl group, or sulfamoyl group. Represents. Of these, a hydrogen atom, an aromatic group, a heterocyclic group, an acyl group, an alkyl or arylsulfonyl group is preferable, and a hydrogen atom, an aromatic group, and a heterocyclic group are particularly preferable.

Z ² represents a hydrogen atom, an aliphatic group, an aromatic group, or a heterocyclic group.
Q represents a hydrogen atom, an aliphatic group, an aromatic group, or a heterocyclic group. Among them, Q is preferably a group consisting of a nonmetallic atom group necessary for forming a 5- to 8-membered ring. The 5- to 8-membered ring may be substituted, may be a saturated ring, or may have an unsaturated bond. Of these, aromatic groups and heterocyclic groups are particularly preferred. Preferred nonmetallic atoms include nitrogen atoms, oxygen atoms, sulfur atoms or carbon atoms. Specific examples of such a ring structure include, for example, a benzene ring, cyclopentane ring, cyclohexane ring, cycloheptane ring, cyclooctane ring, cyclohexene ring, pyridine ring, pyrimidine ring, pyrazine ring, pyridazine ring, triazine ring, imidazole ring. , Benzimidazole ring, oxazole ring, benzoxazole ring, thiazole ring, benzothiazole ring, oxane ring, sulfolane ring and thiane ring.

Each group described as a substituent in formula (M-II) may further have a substituent. When each of these groups further has a substituent, examples of the substituent include the substituents described in the general formula (MI), the groups exemplified for G, R ¹ and R ² , and ionic hydrophilic groups. It is done.

  Examples of the electron-withdrawing group having a Hammett substituent constant σp value of 0.60 or more include a cyano group, a nitro group, and an alkylsulfonyl group (for example, a methanesulfonyl group and an arylsulfonyl group (for example, a benzenesulfonyl group)). As the electron withdrawing group having a Hammett σp value of 0.45 or more, in addition to the above, an acyl group (for example, acetyl group), an alkoxycarbonyl group (for example, dodecyloxycarbonyl group), an aryloxycarbonyl group (for example, m-chlorophenoxy) Carbonyl), alkylsulfinyl group (for example, n-propylsulfinyl), arylsulfinyl group (for example, phenylsulfinyl), sulfamoyl group (for example, N-ethylsulfamoyl, N, N-dimethylsulfamoyl), halogenated alkyl group (For example, a trif Examples of the electron withdrawing group having a Hammett substituent constant σp value of 0.30 or more include acyloxy groups (for example, acetoxy), carbamoyl groups (for example, N-ethylcarbamoyl, N , N-dibutylcarbamoyl), halogenated alkoxy group (for example, trifluoromethyloxy), halogenated aryloxy group (for example, pentafluorophenyloxy), sulfonyloxy group (for example, methylsulfonyloxy group), halogenated alkylthio group ( For example, difluoromethylthio), an aryl group substituted with an electron-withdrawing group having two or more σp values of 0.15 or more (for example, 2,4-dinitrophenyl, pentachlorophenyl), and a heterocycle (for example, 2 -Benzoxazolyl, 2-benzothiazolyl, 1-phenyl- 2-benzimidazolyl) Specific examples of the electron-withdrawing group having a σp value of 0.20 or more include a halogen atom in addition to the above.

Particularly preferred combinations of substituents for the compound represented by formula (M-I) are as follows.
R ⁵ and R ⁶ are preferably a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group, a sulfonyl group or an acyl group, more preferably a hydrogen atom, an aryl group, a heterocyclic group or a sulfonyl group, most preferably Is a hydrogen atom, an aryl group, or a heterocyclic group. However, R ⁵ and R ⁶ are not both hydrogen atoms.

  G is preferably a hydrogen atom, a halogen atom, an alkyl group, a hydroxyl group, an amino group, or an acylamino group, more preferably a hydrogen atom, a halogen atom, an amino group, or an acylamino group, and most preferably a hydrogen atom, an amino group. Group, an acylamino group.

  Of A, a pyrazole ring, an imidazole ring, an isothiazole ring, a thiadiazole ring, and a benzothiazole ring are preferable, a pyrazole ring and an isothiazole ring are more preferable, and a pyrazole ring is most preferable.

B ¹ and B ² are each -CR ¹ =, - CR ² = Yes, R ¹ and R ² are each preferably a hydrogen atom, an alkyl group, a halogen atom, a cyano group, a carbamoyl group, a carboxyl group, a hydroxyl group , An alkoxy group and an alkoxycarbonyl group, and more preferably a hydrogen atom, an alkyl group, a carboxyl group, a cyano group and a carbamoyl group.

  Preferable structures of the cyan dye include compounds represented by the following general formula (CI).

In the general formula (CI), X ¹ , X ² , X ³ and X ⁴ each independently represents an electron-withdrawing group having σp of 0.40 or more. Y ¹ , Y ² , Y ³ and Y ⁴ each independently represent a monovalent substituent. M represents a hydrogen atom, a metal element or an oxide, hydroxide or halide thereof. ^{a 1 ~a 4, b 1 ~b} 4 are each X ¹ to X ^4, and represents the number of substituents Y ¹ to Y ^4.
a ¹ ~a ⁴ each independently represent an integer of 0 to 4, b ¹ ~b ⁴ each independently represents an integer of 0-4. However, the sum of a ^{1 to} a ⁴ is 2 or more, preferably 3 or more, and most preferably a ¹ = a ² = a ³ = a ⁴ = 1.
When the dye is a water-soluble dye, an ionic hydrophilic group is further added as a substituent at any position on X ¹ , X ² , X ³ , X ⁴ , Y ¹ , Y ² , Y ³ , Y ^4. It is preferable to have. Examples of the ionic hydrophilic group as a substituent include a sulfo group, a carboxyl group, a phosphono group, and a quaternary ammonium group.

  Among the compounds represented by the general formula (CI) (phthalocyanine dyes), the compounds represented by the following general formula (C-II) (phthalocyanine dyes) are more preferable. Hereinafter, the compound (phthalocyanine dye) represented by the general formula (C-II) will be described in detail.

In General Formula (C-II), X ^{11 to} X ¹⁴ each independently represent —SO—Z, —SO ₂ —Z, —SO ₂ NR ²¹ R ²² , a sulfo group, —CONR ²¹ R ²² , or — Represents CO ₂ R ¹ . Y ^{11 to} Y ¹⁸ each independently represent a monovalent substituent. M is a hydrogen atom, a metal atom or an oxide, hydroxide or halide thereof. a11~a14 each represent a number of substituents X ¹¹ to X ¹⁴ each independently represents an integer of 1 or 2. Z is each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, substituted or unsubstituted Represents an unsubstituted heterocyclic group. R ²¹ and R ²² are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aralkyl group, substituted or unsubstituted A substituted aryl group or a substituted or unsubstituted heterocyclic group is represented.

General formula (C-II) in, a ¹¹ ~a ¹⁴ each independently represent an integer of 1 or 2, particularly preferred are ^{4 ≦ a 11 + a 12 +} a 13 + a 14 ≦ 6, Among them Preferred is when a ¹¹ = a ¹² = a ¹³ = a ¹⁴ = 1.

X ¹¹ , X ¹² , X ¹³ and X ¹⁴ may each be the same substituent or, for example, X ¹¹ , X ¹² , X ¹³ and X ¹⁴ are all —SO ₂ —Z, but each Z is As in the case of including different ones, they may be the same type of substituents but may be partially different from each other, or, for example, —SO ₂ —Z and —SO ₂ NR ²¹ R ²² are substituted at the same time. As in the case, they may contain different substituents.

  Among the compounds (phthalocyanine dyes) represented by the general formula (C-II), particularly preferred combinations of substituents are as follows.

X ^{11 to} X ¹⁴ are each preferably —SO—Z, —SO ₂ —Z, —SO ₂ NR ²¹ R ²² , or —CONR ²¹ R ²² , particularly —SO ₂ —Z or —SO _2. NR ²¹ R ²² is preferred, and —SO ₂ —Z is most preferred.

  Z is preferably each independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group, and among them, a substituted alkyl group, a substituted aryl group, and a substituted heterocyclic group are most preferred. preferable. In particular, the case of having an asymmetric carbon in the substituent (use in a racemic form) is preferable because of increasing the solubility of the dye and the ink stability. Moreover, the case where a hydroxyl group, an ether group, an ester group, a cyano group, an amide group, and a sulfonamide group have in a substituent is preferable from the reason of improving associative property and improving fastness.

R ²¹ and R ²² are each independently preferably a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group, and among them, a hydrogen atom, a substituted alkyl group, A substituted aryl group and a substituted heterocyclic group are most preferred. However, it is not preferable that both R ¹ and R ² are hydrogen atoms. In particular, the case of having an asymmetric carbon in the substituent (use in a racemic form) is preferable because of increasing the solubility of the dye and the ink stability. In addition, for the reason of increasing the association property and improving the fastness, it is preferable that a hydroxyl group, an ether group, an ester group, a cyano group, an amide group, or a sulfonamide group have in the substituent.

Y ^{11 to} Y ¹⁸ are a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a cyano group, an alkoxy group, an amide group, a ureido group, a sulfonamide group, a carbamoyl group, a sulfamoyl group, an alkoxycarbonyl group, a carboxyl group, and a sulfo group. In particular, a hydrogen atom, a halogen atom, a cyano group, a carboxyl group, and a sulfo group are preferable, and a hydrogen atom is most preferable. a ^{11 to} a ¹⁴ are each independently preferably 1 or 2, particularly preferably all 1. M represents a hydrogen atom, a metal element or an oxide, hydroxide or halide thereof, and Cu, Ni, Zn, and Al are particularly preferable, and Cu is particularly preferable.

  As for the preferred combination of substituents of the compound represented by formula (C-II), a compound in which at least one of various substituents is the above preferred group is preferable, and more various substituents are the above preferred groups. Are more preferred, and compounds in which all substituents are the preferred groups are most preferred.

  As the chemical structure of the phthalocyanine dye preferably used in the present invention, an electron-withdrawing group such as a sulfinyl group, a sulfonyl group, and a sulfamoyl group is substituted on each of the four benzene rings of the phthalocyanine to replace the entire phthalocyanine skeleton. It is preferable to introduce the group so that the total σp value of the group is 1.6 or more.

  The compound represented by the general formula (CI) is inevitably different in the introduction position and number of substituents Xn (n = 1 to 4) and Ym (m = 1 to 4) depending on the synthesis method. Mixtures are common, so the general formula often represents a statistical average of these analog mixtures. In the present invention, it has been found that a specific mixture is particularly preferable when these analog mixtures are classified into the following three types. That is, the phthalocyanine dye analog mixture, which is a compound represented by the general formulas (CI) and (C-II), is defined by classifying into the following three types based on the substitution position.

  (1) β-position substitution type: phthalocyanine dye having a specific substituent at the 2 and / or 3 position, the 6 and / or 7 position, the 10 and / or 11 position, the 14 and / or 15 position.

  (2) α-position substitution type: phthalocyanine dye having a specific substituent at 1 and / or 4 position, 5 and / or 8 position, 9 and / or 12 position, 13 and / or 16 position.

  (3) α, β-position mixed substitution type: phthalocyanine dye having a specific substituent without regularity at positions 1 to 16.

  In the present specification, when describing derivatives of phthalocyanine dyes having different structures (particularly, different substitution positions), the β-position substitution type, α-position substitution type, and α, β-position mixed substitution type are used. .

  Examples of the phthalocyanine derivative used in the present invention include “Phthalocyanine—Chemistry and Function” (P. 1-62), C.K. C. Leznoff-A. B. P. Lever co-authored by VCH and published in 'Phthalogicanes-Properties and Applications' (P. 1-54), etc., can be synthesized by combining quoted or similar methods.

  The compounds represented by the general formula (CI) in the present invention (phthalocyanine dyes) are disclosed in International Publications WO 00/17275, 00/08103, 00/08101, 98/41853, and JP-A-10-36471. As described, it can be synthesized through sulfonation, sulfonyl chlorideation, and amidation reaction of an unsubstituted phthalocyanine compound, for example. In this case, sulfonation can occur at any position of the phthalocyanine nucleus, and the number of sulfonation is difficult to control. Therefore, when a sulfo group is introduced under such reaction conditions, the position and number of the sulfo group introduced into the product cannot be specified, and a mixture in which the number of substituents and the substitution position are different is always given. Therefore, when synthesizing the compound of the present invention using it as a raw material, the number and substitution position of the heterocyclic substituted sulfamoyl group cannot be specified, so the compound of the present invention includes several types of compounds having different numbers of substituents and substitution positions. Α, β-position mixed substitution mixture.

  As described above, for example, when a large number of electron withdrawing groups such as sulfamoyl groups are introduced into the phthalocyanine nucleus, the oxidation potential becomes more noble and the ozone resistance is enhanced. According to the above synthesis method, it is inevitable that a small amount of electron-withdrawing groups are introduced, that is, a phthalocyanine dye having a lower oxidation potential is mixed. Therefore, in order to improve ozone resistance, it is more preferable to use a synthesis method that suppresses the formation of a compound having a lower oxidation potential.

  In contrast, the compound (phthalocyanine dye) represented by the general formula (CI) in the present invention is, for example, a phthalonitrile derivative (compound P) and / or a diiminoisoindoline derivative (compound) represented by the following formula: It is obtained by reacting Q) with a metal derivative represented by the general formula (C-III). Alternatively, it can be derived from a tetrasulfophthalocyanine compound obtained by reacting a 4-sulfophthalic acid derivative (compound R) represented by the following formula and a metal derivative represented by the general formula (C-III).

In the above formulas, Xp corresponds to X ¹ , X ² , X ³ , or X ⁴ in the general formula (C-II). Yq and Yq ′ correspond to Y ¹¹ , Y ¹² , Y ¹³ , Y ¹⁴ , Y ¹⁵ , Y ¹⁶ , Y ¹⁷ , or Y ¹⁸ in the general formula (C-II), respectively.

Formula (C-III)
M- (Y) _d
In general formula (C-III), M has the same meaning as M in the compound represented by general formula (CI), and Y is a monovalent group such as a halogen atom, acetate anion, acetylacetonate, oxygen, and the like. Or a bivalent ligand is shown, d is an integer of 1-4.

  That is, according to the above synthesis method, a specific number of desired substituents can be introduced. In particular, when a large number of electron withdrawing groups are to be introduced to make the oxidation potential noble as in the present invention, the above synthesis method is compared with the synthesis method of the compound represented by the general formula (CI). It is extremely excellent.

  The compounds represented by the above general formula (CI) obtained as described above are usually the following general formulas (C-II-1) to (C-II-) which are isomers at each substitution position of Xp. It is a mixture of compounds represented by 4), that is, β-position substitution type.

In the above synthesis method, if the same Xp is used, a β-position-substituted phthalocyanine dye in which X ¹¹ , X ¹² , X ¹³ and X ¹⁴ are exactly the same substituents can be obtained. On the other hand, by using different combinations of Xp, it is possible to synthesize dyes having the same type of substituents but partially different from each other, or dyes having different types of substituents. . Among the dyes of the general formula (C-II), these dyes having different electron-withdrawing substituents are particularly preferable because they can adjust the solubility of the dye, the associability, the stability with time of the ink, and the like.

  In the present invention, it is found that it is very important to improve the fastness that the oxidation potential is noble than 1.0 V (vs SCE) in any substitution type. It was completely unpredictable from the prior art. Although the cause is unknown in detail, the β-position substitution type tends to be clearly superior in terms of hue, light fastness, ozone gas resistance, etc., compared to the α, β-position mixed substitution type. .

  The phthalocyanine dyes which are compounds represented by the general formulas (CI) and (C-II) can be synthesized according to the above-mentioned patents, and Japanese Patent Application Nos. 2001-226275 and 2001-96610. , 2001-47013, and 2001-193638. Further, the starting material, dye intermediate and synthetic route are not limited by these.

  Magenta dyes and cyan dyes as oil-soluble compounds used in the present invention are characterized by having an oxidation potential nobler than 0.8 V, but phthalocyanines widely used as cyan dyes form aggregates. Therefore, the fastness can be compensated even if the oxidation potential is somewhat low, whereas the magenta dye does not form an association, so in order to increase the fastness, the oxidation potential can be set higher than the cyan dye. preferable.

  Examples of the oil-soluble dye that can be suitably used in the present invention include Y-1 to Y-35, M-1 to M-26, and C-1 to C-50 described in JP-A-2003-238863. These are for explaining the present invention in detail, and the present invention is not limited by these. The oxidation potential of the oil-soluble dye is shown in parentheses.

  Other examples of the compound in the present invention include JP-A No. 2002-294097, Japanese Patent Application Nos. 2001-24352, 2002-249777, 2002-256167, 2002-275386, 2003-12952, Although described also in each gazette or specification of 2001-279145, 2002-309116, and Japanese Patent Application No. 2001-110335, it is not limited to these. The compounds of the present invention can be easily synthesized by the methods described in the patents listed here.

  In the ink composition of the present invention, it is preferable that at least one of the oil-soluble dyes used is a compound represented by the general formula (MI) or the general formula (CI).

  As content in the ink composition of the oil-soluble dye used for this invention, 0.2-20 mass% is preferable with respect to an ink composition, and 0.5-10 mass% is more preferable.

(UV absorber)
Next, the ultraviolet absorbent used in the present invention will be described in detail.
The ultraviolet absorber is used for the purpose of improving the storability of an image, and the ultraviolet absorber is not particularly limited, and an antioxidant described later is added together with the oil-soluble compound as necessary. It is preferably used after being emulsified and dispersed. Among them, benzophenone-based UV absorbers, benzotriazole-based UV absorbers, oxalic anilide-based UV absorbers, cyanoacrylate-based UV absorbers, triazine-based UV absorbers, etc. are used alone or in combination. It is preferable.

  Specific examples of the ultraviolet absorber include, for example, 2- (5-methyl-2′-hydroxyphenyl) benzotriazole, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl]. -2H-benzotriazole, 2- (3,5-di-tbutyl-2-hydroxyphenyl) benzotriazole, 2- (3-t-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole 2- (3,5-di-t-butyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3,5-di-t-amyl-2-hydroxyphenyl) benzotriazole, 5-t -Butyl-3- (5-chloro-2H-benzotriazol-2-yl) -4-hydroxybenzenepropionic acid octyl ester, 2- (2'-hydride) Benzotriazole ultraviolet absorbers such as Roxy-3′-n-dodecyl-5′-methyl) phenylbenzotriazole; Benzophenone ultraviolet absorbers such as 2-hydroxy-4-methoxybenzophenone and 2-hydroxy-4-octoxybenzophenone Agents and the like.

  As the benzotriazole-based ultraviolet absorber, those that are solid at room temperature may be used, but from the viewpoint of production and the like, it is preferable to use those that are liquid at room temperature. Specific examples of such a benzotriazole ultraviolet absorber that is liquid at room temperature are described in detail in JP-B-55-36984, JP-A-55-12587, and JP-A-58-214152. Other preferred benzotriazole ultraviolet absorbers are disclosed in JP-A Nos. 58-212844, 59-46646, 59-109055, JP-A 36-10466, and 42-26187. 48-5496, 48-41572, U.S. Pat. Nos. 3,754,919, and 4,220,711.

  Specific examples of the benzophenone-based ultraviolet absorber include U.S. Pat. No. 3,707,375, Japanese Patent Publication No. 48-30492, Japanese Patent Publication Nos. 47-10537, 58-111942, 59-19945, and 63-. The thing described in each gazettes, such as 53544, or what was synthesize | combined according to the method described in these can be mentioned. In addition to the above, ultraviolet absorbers that can be used in the present invention are described in detail in JP-A-4-19778.

  The ultraviolet absorber is further described in JP-A-58-185679, JP-A-61-190537, JP-A-2-782, JP-A-5-97075, JP-A-9-34057, and the like. Benzotriazole compounds, benzophenone compounds described in JP-A No. 46-2784, JP-A No. 5194443, US Pat. No. 3,214,463, etc., JP-B No. 48-30492, No. 56-21141 Cinnamic acid compounds described in JP-A-10-88106, JP-A-4-298503, JP-A-8-53427, JP-A-8-239368, JP-A-10-182621, Special Tables The triazine compounds described in JP-A-8-501291, Research Disclosure No. Examples thereof include compounds described in No. 24239, compounds that emit fluorescence by absorbing ultraviolet rays typified by stilbene and benzoxazole compounds, so-called fluorescent brighteners, and the like.

In the present invention, the amount of the ultraviolet absorber used is preferably 0.001 to 100 parts, more preferably 0.01 to 10 parts, and particularly preferably 0.1 parts to 1 part with respect to 1 part of the oil-soluble compound. 5.0 parts is most preferred.
In addition, it is effective to be present in the vicinity of the dye molecule as the usage form, and the ultraviolet absorber may be added by emulsifying alone, but in particular, an embodiment in which it is emulsified and dispersed after being dissolved together with the dye. Is most preferred.

  Although the specific example of the ultraviolet absorber suitably used for this invention is shown below, this invention is not limited to these specific examples.

(Antioxidant)
Next, the antioxidant used in the present invention will be described in detail. The antioxidant is used for the purpose of improving the storage stability of the image. The antioxidant is not particularly limited, and an ultraviolet absorber is preferably added together with the oil-soluble compound described above, preferably. Is used after being emulsified and dispersed. Among these, at least one selected from the group consisting of phenols, phosphites, hindered amines, and thioethers is preferable.

  Specific examples of the antioxidant include, for example, triethylene glycol-bis (3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate, 1,6-hexanediol-bis (3- ( 3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 3,5-di-tert-butyl-4-hydroxy-benzylphosphonate-diethyl ester, 2,6-di-tert-butyl-4 -Methylphenol, styrenated phenol, 2,2'-methylenebis (4-methyl-6-tert-butylphenol), 4,4'-butylidenebis (3-methyl-6-tert-butylphenol), dilauryl-3,3 ' -Thiodipropionate, distearyl-3,3'-thiodipropionate, tolylnonylphenol phosphite, triphenylphenol And sphite, 2-mercaptobenzimidazole, tetrakis (methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate) methane, and the like, among others, 3,5-di-t- Butyl-4-hydroxy-benzylphosphonate-diethyl ester, triethylene glycol-bis (3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate is preferred.

  In addition, hindered amines include dimethyl succinate-1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate, poly [(6- (1,1,3 , 3-tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl) ((2,2,6,6-tetramethyl-4-piperidyl) imino) hexamethylene ((2,2, 6,6-tetramethyl-4-piperidyl) imino)], N, N′-bis (3-aminopropyl) ethylenediamine-2,4-bis (N-butyl-N- (1,2,2,6, 6-pentamethyl-4-piperidyl) amino) -6-chloro-1,3,5-triazine condensate, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2, 2,6,6-pentamethy -4-piperidinyl) sebacate, 2- (3,5-t-butyl-4-hydroxybenzyl) -2-n-butylmalonate bis (1,2,2,6,6-pentamethyl-4-piperidyl), etc. Is mentioned.

  In the present invention, the amount of the antioxidant used is preferably 0.001 to 100 parts, more preferably 0.01 to 10 parts, and more preferably 0.1 to 5.0 parts relative to 1 part of the oil-soluble compound. Is particularly preferred. In addition, as a use form, it is effective to be present in the vicinity of the oil-soluble compound, and the antioxidant may be added by emulsifying alone, but in particular, the emulsification is performed after dissolving with the oil-soluble compound. The dispersion mode is most preferable.

(Hydrophobic polymer)
The fine particle dispersion in the present invention preferably includes a hydrophobic polymer. There is no restriction | limiting in particular as said hydrophobic polymer, A conventionally well-known thing can be suitably selected according to the objective. Examples thereof include vinyl polymers and condensation polymers (polyurethane, polyester, polyamide, polyurea, polycarbonate). The hydrophobic polymer in the present invention includes both water-insoluble and water-dispersed (self-emulsifiable) polymers, and these polymers are preferably used from the viewpoint of ease of production of fine particles and dispersion stability. Used.

  The water-dispersed polymer may be either an ion dissociation type, a non-ionic dispersible group-containing type, or a mixture thereof. Examples of the ion dissociation type polymer include a polymer having a cationic dissociation group such as a tertiary amino group and a polymer having an anionic dissociation group such as carboxylic acid and sulfonic acid. Examples of the nonionic dispersible group-containing polymer include polymers containing a nonionic dispersible group such as a polyethyleneoxy group. Among these, from the viewpoint of dispersion stability of the fine particles, an ion dissociation type polymer containing an anionic dissociable group, a nonionic dispersible group containing type polymer, and a mixed type polymer thereof are preferable.

Details of the vinyl polymer will be described.
As a monomer which forms a vinyl polymer, the following are mentioned, for example.
That is, acrylic acid esters and methacrylic acid esters (the ester group is an alkyl group or aryl group which may have a substituent, such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group) Group, sec-butyl group, tert-butyl group, hexyl group, 2-ethylhexyl group, tert-octyl group, 2-chloroethyl group, cyanoethyl group, 2-acetoxyethyl group, tetrahydrofurfuryl group, 5-hydroxypentyl group, Cyclohexyl group, benzyl group, hydroxyethyl group, 3-methoxybutyl group, 2- (2-methoxyethoxy) ethyl group, 2,2,2-trifluoroethyl group, 1H, 1H, 2H, 2H-perfluorodecyl group , Phenyl group, 2,4,5-trimethylphenyl group, 4-chlorophenyl group, etc.)

Vinyl esters, specifically, aliphatic carboxylic acid vinyl esters which may have a substituent (for example, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl caproate, vinyl chloro) Acetate), and aromatic carboxylic acid vinyl esters (for example, vinyl benzoate, vinyl 4-methylbenzoate, vinyl salicylate, etc.) that may have a substituent.
Acrylamides, specifically, acrylamide, N-monosubstituted acrylamide, N-disubstituted acrylamide (substituent is an alkyl group, aryl group, silyl group which may have a substituent, for example, methyl group, n -Propyl group, isopropyl group, n-butyl group, tert-butyl group, tert-octyl group, cyclohexyl group, benzyl group, hydroxymethyl group, alkoxymethyl group, phenyl group, 2,4,5-trimethylphenyl group, 4 -Chlorophenyl group, trimethylsilyl, etc.).

Methacrylamide, specifically, methacrylamide, N-monosubstituted methacrylamide, N-disubstituted methacrylamide (substituent is an alkyl group, aryl group, silyl group which may have a substituent, Methyl group, n-propyl group, isopropyl group, n-butyl group, tert-butyl group, tert-octyl group, cyclohexyl group, benzyl group, hydroxymethyl group, alkoxymethyl group, phenyl group, 2,4,5-trimethyl Phenyl group, 4-chlorophenyl group, trimethylsilyl and the like).
Olefins (eg, ethylene, propylene, 1-pentene, vinyl chloride, vinylidene chloride, isoprene, chloroprene, butadiene, etc.), styrenes (eg, styrene, methyl styrene, isopropyl styrene, methoxy styrene, acetoxy styrene, chlorostyrene, etc.) Vinyl ethers (for example, methyl vinyl ether, butyl vinyl ether, hexyl vinyl ether, methoxyethyl vinyl ether, etc.).

Other monomers include crotonic acid ester, itaconic acid ester, maleic acid diester, fumaric acid diester, methyl vinyl ketone, phenyl vinyl ketone, methoxyethyl vinyl ketone, N-vinyl oxazolidone, N-vinyl pyrrolidone, vinylidene chloride, methylene malon nitrile Vinylidene, diphenyl-2-acryloyloxyethyl phosphate, diphenyl-2-methacryloyloxyethyl phosphate, dibutyl-2-acryloyloxyethyl phosphate, dioctyl-2-methacryloyloxyethyl phosphate, and the like.
Examples of the monomer having a dissociable group include a monomer having an anionic dissociable group and a monomer having a cationic dissociable group. Examples of the monomer having an anionic dissociable group include a carboxylic acid monomer, a sulfonic acid monomer, and a phosphoric acid monomer.

  Examples of the carboxylic acid monomer include acrylic acid, 2-carboxyethyl acrylate, methacrylic acid, itaconic acid, maleic acid, fumaric acid, citraconic acid, crotonic acid, and itaconic acid monoalkyl esters (for example, monomethyl itaconic acid and monoethyl itaconic acid). , Monobutyl itaconate, etc.), monoalkyl maleate (eg, monomethyl maleate, monoethyl maleate, monobutyl maleate, etc.).

  Examples of the sulfonic acid monomer include styrene sulfonic acid, vinyl sulfonic acid, acryloyloxyalkanesulfonic acid (for example, acryloyloxyethanesulfonic acid, acryloyloxypropanesulfonic acid, etc.), and methacryloyloxyalkanesulfonic acid (for example, acryloyloxyethanesulfone). Acid, acryloyloxypropanesulfonic acid, etc.), acrylamide alkanesulfonic acid (for example, 2-acrylamido-2-methylethanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-acrylamido-2-methylbutanesulfonic acid, etc.) ), Methacrylamide alkanesulfonic acid (for example, 2-methacrylamido-2-methylethanesulfonic acid, 2-methacrylamide-2-methylpropanesulfonic acid) And 2-methacrylamide-2-methylbutanesulfonic acid).

Examples of the phosphoric acid monomer include vinylphosphonic acid and methacryloyloxyethanephosphonic acid.
Among these, acrylic acid 2-carboxyethyl acrylate, methacrylic acid, styrene sulfonic acid, vinyl sulfonic acid, acrylamide alkyl sulfonic acid, and methacrylamide alkyl sulfonic acid are preferable, and acrylic acid, 2-carboxyethyl acrylate, methacrylic acid, styrene sulfone are preferred. Acid and 2-acrylamido-2-methylpropanesulfonic acid are more preferable, and acrylic acid, 2-carboxyethyl acrylate, and 2-acrylamido-2-methylpropanesulfonic acid are particularly preferable.

Examples of the monomer having a cationic dissociable group include monomers having a tertiary amino group such as dialkylaminoethyl methacrylate and dialkylaminoethyl methacrylate. Examples of the monomer containing a nonionic dispersible group include an ester of polyethylene glycol monoalkyl ether and a carboxylic acid monomer, an ester of polyethylene glycol monoalkyl ether and a sulfonic acid monomer, polyethylene glycol monoalkyl ether and phosphorus. Examples thereof include an ester with an acid monomer, a vinyl group-containing urethane formed from a polyethylene glycol monoalkyl ether and an isocyanate group-containing monomer, and a macromonomer containing a polyvinyl alcohol structure.
As a repeating number of the ethyleneoxy part of polyethyleneglycol monoalkyl ether, 8-50 are preferable and 10-30 are more preferable. The number of carbon atoms in the alkyl group of the polyethylene glycol monoalkyl ether is preferably 1-20, and more preferably 1-12.

Next, the condensation polymer will be described in detail.
The polyurethane is basically synthesized by a polyaddition reaction using a diol compound and a diisocyanate compound as raw materials. Specific examples of the diol compound include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 2,3-butanediol, and 2,2-dimethyl-diol as non-dissociable diols. 1,3-propanediol, 1,4-pentanediol, 2,4-pentanediol, 3,3-dimethyl-1,2-butanediol, 2-ethyl-2-methyl-1,3-propanediol, 1,6- Hexanediol, 2,5-hexanediol, 2-methyl-2,4-pentanediol, 2,2-diethyl-1,3-propanediol, 2,4-dimethyl-2,4-pentanediol, 2-methyl-2-propyl- 1,3-propanediol, 2,5-dimethyl-2,5-hexanediol, 2-ethyl-1,3-hexane All, 1,2-octanediol, 2,2,4-trimethyl-1,3-pentanediol, 1,4-cyclohexanedimethanol, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, polyethylene glycol (average molecular weight = 200,300,400,600,1000,1500,4000), polypropylene glycol (average molecular weight = 200,400,1000), polyester polyol, 4,4′-dihydroxy-diphenyl-2,2-propane, 4,4 Examples include '-dihydroxyphenyl sulfone.

  Examples of the diol having an anionic group include 2,2-bis (hydroxymethyl) propionic acid, 2,2-bis (hydroxymethyl) butanoic acid, 2,5,6-trimethoxy-3,4-dihydroxyhexanoic acid, Examples include 3-dihydroxy-4,5-dimethoxypentanoic acid, 2,4-di (2-hydroxy) ethyloxycarbonylbenzenesulfonic acid, and salts thereof, but are not particularly limited thereto.

Preferred specific examples of the diisocyanate include ethylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, 1,4-cyclohexane diisocyanate, 2,4-toluene diisocyanate, 1,3-xylylene diisocyanate, 1,5-naphthalene diisocyanate, m-phenylene. Examples include diisocyanate, p-phenylene diisocyanate, 3,3′-dimethyl-4,4′-diphenylmethane diisocyanate, 3,3′-dimethylbiphenylene diisocyanate, dicyclohexylmethane diisocyanate, and methylenebis (4-cyclohexylisocyanate).

  The polyester is basically synthesized by dehydration condensation of a diol compound and a dicarboxylic acid compound. Specific examples of the dicarboxylic acid compound include oxalic acid, malonic acid, succinic acid, glutaric acid, dimethylmalonic acid, adipic acid, pimelic acid, α, α-dimethylsuccinic acid, acetone dicarboxylic acid, sebacic acid, 1, 9-nonanedicarboxylic acid, fumaric acid, maleic acid, itaconic acid, citraconic acid, phthalic acid, isophthalic acid, terephthalic acid, 2-butyl terephthalic acid, tetrachloroterephthalic acid, acetylenedicarboxylic acid, poly (ethylene terephthalate) dicarboxylic acid, Examples include 1,2-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, ω-poly (ethylene oxide) dicarboxylic acid, p-xylylene dicarboxylic acid, and the like. These compounds may be used in the form of an alkyl ester of a dicarboxylic acid (for example, dimethyl ester) or an acid chloride of a dicarboxylic acid when performing a polycondensation reaction with a diol compound, or maleic anhydride or succinic anhydride. Alternatively, it may be used in the form of an acid anhydride such as phthalic anhydride.

Preferred examples of the dicarboxylic acid having a sulfonic acid group and the diol raw material include sulfophthalic acids (3-sulfophthalic acid, 4-sulfophthalic acid, 4-sulfoisophthalic acid, 5-sulfoisophthalic acid, 2-sulfoterephthalic acid), sulfosuccinic acid Sulfonaphthalenedicarboxylic acids (4-sulfo-1,8-naphthalenedicarboxylic acid, 7-sulfo-1,5-naphthalenedicarboxylic acid, etc.), 2,4-di (2-hydroxy) ethyloxycarbonylbenzenesulfonic acid, and these Salt can be mentioned.
As the diol compound, a compound selected from the same group as the diols described in the polyurethane can be used.

  A typical method for synthesizing the polyester is a condensation reaction of the diol compound and a dicarboxylic acid or a derivative thereof, but it can also be obtained by condensing a hydroxycarboxylic acid (for example, 12-hydroxystearic acid) or a cyclic ether. Can also be suitably used in the present invention. Polyesters obtained by methods such as ring-opening polymerization of lactones and lactones (lecture polymerization reaction theory 6 ring-opening polymerization (I) detailed by Takeo Saegusa (Chemical Doujin, 1971)) can be used. .

The polyamide is obtained by polycondensation of a diamine compound and a dicarboxylic acid compound, polycondensation of an aminocarboxylic acid compound, or ring-opening polymerization of lactams.
Examples of the diamine compound include ethylenediamine, 1,3-propanediamine, 1,2-propanediamine, hexamethylenediamine, octamethylenediamine, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, piperazine, 2,5- Examples include dimethylpiperazine, 4,4′-diaminodiphenyl ether, 3,3′-diaminodiphenylsulfone, xylylenediamine, etc. Examples of aminocarboxylic acids include glycine, alanine, phenylalanine, ω-aminohexanoic acid, ω-aminodecane. Examples include acids, ω-aminoundecanoic acid, and anthranilic acid. Moreover, (epsilon) -caprolactam, azetidinone, a pyrrolidone etc. can be mentioned as a monomer which can be used for ring-opening polymerization.
As the dicarboxylic acid compound, a compound selected from the same group as the dicarboxylic acids described in the above polyester can be used.

  The polyurea can be basically obtained by polyaddition of a diamine compound and a diisocyanate compound or a deammonia reaction of a diamine compound and urea. The diamine compound as a raw material is the diamine described in the above polyamide, and the diisocyanate compound is in the above polyurethane. Compounds selected from the same group as the described diisocyanates can be used.

  The polycarbonate can be basically obtained by reacting a diol compound with phosgene or a carbonate ester derivative (for example, an aromatic ester such as diphenyl carbonate), and the diol compound as a raw material is the diol compound described in the polyurethane. Compounds from the same group can be used.

The hydrophobic polymer in the present invention may use one kind of necessary constituent raw materials, and various purposes (for example, adjustment and solubility of polymer glass transition temperature (Tg), compatibility with dyes, dispersion) Depending on the stability), two or more of them can be used in any proportion.
Among the hydrophobic polymers, those having the dissociable group are preferable from the viewpoint of dispersion stability of fine particles, those having at least one of a carboxyl group and a sulfonic acid group are more preferable as the dissociable group, and the dissociable group is Those having a carboxyl group are particularly preferred.

  Further, after the polymerization of each polymer, a reactive group such as a hydroxy group or an amino group can be introduced by acting a compound capable of introducing a dissociation group by a reaction such as an acid anhydride (for example, maleic anhydride). . The content of the dissociable group is preferably from 0.1 to 3.0 mmol / g, and more preferably from 0.2 to 2.0 mmol / g. When the content of the dissociable group is small, the self-emulsifying property of the polymer is small, and when the content is large, the water solubility is high and the polymer tends to be unsuitable for dispersing the dye.

In addition, as the dissociating group, the anionic dissociating group may be an alkali metal (for example, Na, K, etc.) or a salt of ammonium ion, and the cationic dissociating group is further It may be a salt of an organic acid (for example, acetic acid, propionic acid, methanesulfonic acid) or an inorganic acid (hydrochloric acid, sulfuric acid, etc.).
Among the oil-soluble polymers, vinyl polymers, polyurethanes, and polyesters are particularly preferable in view of imparting compatibility with oil-soluble compounds and ease of introduction of dissociable groups from the viewpoint of imparting excellent dispersion stability.

  Specific examples (PA-1) to PA-38)) of the vinyl polymer are listed below. The ratio in parentheses means the mass ratio. The present invention is not limited to these specific examples.

(PA-1) Methyl methacrylate-ethyl acrylate copolymer (50:50)
(PA-2) Butyl acrylate-styrene copolymer (50:50)
(PA-3) poly n-butyl methacrylate (PA-4) polyisopropyl methacrylate (PA-5) poly (4-tert-butylphenyl acrylate)

(PA-6) n-butyl methacrylate-N-vinyl-2-pyrrolidone copolymer (90:10)
(PA-7) Methyl methacrylate-vinyl chloride copolymer (70:30)
(PA-8) Isobutyl methacrylate-butyl acrylate copolymer (55:45)
(PA-9) Vinyl acetate-acrylamide copolymer (85:15)
(PA-10) n-butyl acrylate-methyl methacrylate-n-butyl methacrylate copolymer (35:35:30)

(PA-11) Ethyl methacrylate-n-butyl acrylate copolymer (70:30)
(PA-12) t-Butylacrylamide-n-butyl acrylate copolymer (50:50)
(PA-13) t-Butylacrylamide-n-butyl methacrylate copolymer (50:50)
(PA-14) t-butyl methacrylamide-methyl methacrylate-acrylic acid copolymer (60:30:10)
(PA-15) n-butyl acrylate-acrylic acid copolymer (80:20)

(PA-16) sec-butyl acrylate-acrylic acid copolymer (85:15)
(PA-17) Isopropyl acrylate-acrylic acid copolymer (90:10)
(PA-18) Butyl methacrylate-2-hydroxyethyl methacrylate-acrylic acid copolymer (85: 5: 10)
(PA-19) Isobutyl methacrylate-tetrahydrofurfuryl acrylate-acrylic acid copolymer (60:30:10)
(PA-20) n-butyl methacrylate-1H, 1H, 2H, 2H-perfluorodecyl acrylate-acrylic acid copolymer (75: 20: 5)

(PA-21) Methyl methacrylate-n-butyl acrylate-acrylic acid copolymer (50: 45: 5)
(PA-22) 3-methoxybutyl methacrylate-styrene-acrylic acid copolymer (35:50:15)
(PA-23) Ethyl acrylate-phenyl methacrylate-acrylic acid copolymer (72:15:13)
(PA-24) Methacrylic acid ester-acrylic acid copolymer (70:20:10) of isobutyl methacrylate-polyethylene glycol monomethyl ether (ethyleneoxy chain repeat number 23)
(PA-25) Ethyl methacrylate-acrylic acid copolymer (95: 5)

(PA-26) Isobutyl acrylate-methoxystyrene-acrylic acid copolymer (75:15:10)
(PA-27) Isobutyl acrylate-N-vinyl pyrrolidone-acrylic acid copolymer (60:30:10)
(PA-28) 2,2,2-trifluoroethyl methacrylate-methyl methacrylate copolymer-methacrylic acid copolymer (25:60:15)
(PA-29) Ethyl methacrylate-2-ethoxyethyl methacrylate-methacrylic acid copolymer (70:15:15)
(PA-30) t-butylacrylamide-n-butylacrylate-acrylic acid copolymer (50: 47: 3)

(PA-31) n-butyl methacrylate-diphenyl-2-methacryloyloxyethyl phosphate-methacrylic acid copolymer (80: 5: 15)
(PA-32) n-butyl methacrylate-phenylacrylamide-methacrylic acid copolymer (70:15:15)
(PA-33) n-butyl methacrylate-N-vinylpyrrolidone-methacrylic acid copolymer (70:15:15)
(PA-34) n-butyl methacrylate-styrene sulfonic acid copolymer (90:10)
(PA-35) Isobutyl methacrylate-styrene sulfonic acid copolymer (90:10)

(PA-36) n-butyl methacrylate-2-acrylamido-2-methylethanesulfonic acid copolymer (90:10)
(PA-37) Isobutyl acrylate-n-butyl methacrylate-2-acrylamido-2-methylethanesulfonic acid copolymer (70:20:10)
(PA-38) tert-butyl acrylate-polyethylene glycol monomethyl ether (ethyleneoxy chain repeat number 23) methacrylate ester-2-acrylamido-2-methylpropanesulfonic acid copolymer (60:30:10)

  Specific examples (PC-1) to PC-20)) of the condensation polymers are exemplified below in the form of raw material monomers (PC-12), and PC-17) and later are exemplified in the form of polymers). However, the present invention is not limited to these. All acidic groups in each polymer were expressed in non-dissociated form. In addition, regarding the components produced by the condensation reaction such as polyester and polyamide, the constituent components are all expressed by dicarboxylic acid, diol, diamine, hydroxycarboxylic acid, aminocarboxylic acid and the like regardless of the raw materials. The ratio in parentheses means the mole percentage ratio of each component.

(PC-1) Toluene diisocyanate / ethylene glycol / 1,4-butanediol (50/15/35)
(PC-2) Toluene diisocyanate / hexamethylene diisocyanate / ethylene glycol / polyethylene glycol (Mw = 600) / 1,4-butanediol (40/10/20/10/20)
(PC-3) 4,4′-diphenylmethane diisocyanate / hexamethylene diisocyanate / tetraethylene glycol / ethylene glycol / 2,2-bis (hydroxymethyl) propionic acid (40/10/20/20/10)
(PC-4) 1,5-naphthylene diisocyanate / butanediol / 4,4′-dihydroxy-diphenyl-2,2′-propane / polypropylene glycol (Mw = 400)
) / 2,2-bis (hydroxymethyl) propionic acid (50/20/5/10/15)
(PC-5) Isophorone diisocyanate / diethylene glycol / neopentyl glycol / 2,2-bis (hydroxymethyl) propionic acid (50/20/20/10)

(PC-6) Diphenylmethane diisocyanate / hexamethylene diisocyanate / tetraethylene glycol / butanediol / 2,4-di (2-hydroxy) ethyloxycarbonylbenzenesulfonic acid (40/10/10/33/7)
(PC-7) terephthalic acid / isophthalic acid / cyclohexanedimethanol / 1,4-butanediol / ethylene glycol (25/25/25/15/10)
(PC-8) terephthalic acid / isophthalic acid / 4,4′-dihydroxy-diphenyl-2
2-propane / tetraethylene glycol / ethylene glycol (30/20/20/15/15)
(PC-9) terephthalic acid / isophthalic acid / 4,4′-benzenedimethanol / diethylene glycol / neopentyl glycol (25/25/25/15/10)
(PC-10) terephthalic acid / isophthalic acid / 5-sulfoisophthalic acid / ethylene glycol / neopentyl glycol (24/24/2/25/25)

(PC-11) 11-aminoundecanoic acid (100)
(PC-12) Reaction product of poly (12-aminododecanoic acid) and maleic anhydride (PC-13) Hexamethylenediamine / Adipic acid (50/50)
(PC-14) N, N′-dimethylethylenediamine / adipic acid / cyclohexanedicarboxylic acid (50/20/30)
(PC-15) Toluene diisocyanate / 4,4′-diphenylmethane diisocyanate / hexamethylenediamine (30/20/50)
(PC-16) Hexamethylenediamine / Nonamethylenediamine / Urea (25/25/50)

  The polymer in this invention may be used individually by 1 type, and may use 2 or more types together as needed. As the usage-amount of the polymer used for preparation of the microparticles | fine-particles of this invention, 5-200 mass% is preferable with respect to the oil-soluble compound which coexists in microparticles | fine-particles, and 10-100 mass% is more preferable.

  The fine particle dispersion in the present invention is obtained by dispersing fine particles containing the oil-soluble compound and the polymer in an aqueous medium. The aqueous medium may contain at least water. Specifically, water or a mixture of water and a water-miscible organic solvent, if necessary, a hydrophobic polymer, a surfactant, a drying agent. Preferred are those added with additives such as inhibitor (wetting agent), stabilizer, preservative and the like.

(High boiling point organic solvent)
It is preferable to use a high-boiling organic solvent for the fine particle dispersion in the present invention. The high-boiling organic solvent may be used alone or in combination of two or more (for example, tricresyl phosphate and dibutyl phthalate, trioctyl phosphate and di (2-ethylhexyl) sebacate, etc.). May be.

  Examples of high boiling point organic solvent compounds used in the present invention and / or methods for synthesizing these high boiling point organic solvents include, for example, US Pat. Nos. 2,322,027, 2,533,514, 2,772,163, 2,835,579, 3,594,171, 3,676,137, 3,689,271, 3,700, No. 454, No. 3,748,141, No. 3,764,336, No. 3,765,897, No. 3,912,515, No. 3,936,303, No. 4 No. 4,004,928, No. 4,080,209, No. 4,127,413, No. 4,193,802, No. 4,207,393, No. 4,220,711 No. 4,239,851, No. 4,278,757, No. , 353,979, 4,363,873, 4,430,421, 4,430,422, 4,464,464, 4,483,918 No. 4,540,657, No. 4,684,606, No. 4,728,599, No. 4,745,049, No. 4,935,321, No. 5, No. 013,639, European Patent Nos. 276,319A, 286,253A, 289,820A, 309,158A, 309,159A, 309,160A, 509,311A, 510,576A, East German Patents 147,009, 157,147, 159,573, 225,240A, British Patent 2,091,124A Etc., JP-A-48-473. No. 5, No. 50-26530, No. 51-25133, No. 51-26036, No. 51-27921, No. 51-27922, No. 51-149028, No. 52-46816, No. 53-1520 53-1521, 53-15127, 53-146622, 54-91325, 54-106228, 54-118246, 55-59464, 56-64333, 56-81836, 59-204041, 61-84641, 62-118345, 62-247364, 63-167357, 63-214744, 63-301941, 64-64 No. 9452, No. 64-9454, No. 64-68745, JP-A-1-101543, No. 1-102454, No. 2- No. 792, No. 2-4239, No. 2-43541, No. 4-29237, No. 4-30165, No. 4-232946, No. 4-346338, and the like.

[Preparation of fine particle dispersion]
The fine particle dispersion in the present invention comprises fine particles containing an oil-soluble compound (preferably, an oil-soluble dye), an ultraviolet absorber and / or an antioxidant, and, if necessary, a hydrophobic polymer or a high-boiling organic solvent. It is produced by emulsifying and dispersing in an aqueous medium. Specifically, for example, a method of preparing a latex of a hydrophobic polymer in advance and impregnating the latex with an oil-soluble dye, an ultraviolet absorber and / or an antioxidant, a high-boiling organic solvent, or the like, or a co-emulsification dispersion method, etc. Is mentioned. Among these, the latter co-emulsification dispersion method is preferable.

  The co-emulsification dispersion is obtained by dissolving an oil phase in which the oil-soluble compound, the ultraviolet absorber, the antioxidant, the hydrophobic polymer, and the like are dissolved in a mixed solvent obtained by mixing a high-boiling organic solvent, and optionally a low-boiling organic solvent. It can be carried out by dispersing in an aqueous phase mainly composed of water and forming fine oil droplets of the oil phase. In the co-emulsification dispersion, a method of adding an oil phase to the aqueous phase is common, but a so-called phase inversion emulsification method in which the aqueous phase is dropped into the oil phase can also be preferably used. When emulsifying and dispersing, additives such as surfactants, drying inhibitors, dye stabilizers, emulsion stabilizers, preservatives, and antifungal agents described later are required in either or both of the aqueous phase and the oil phase. It can be added depending on.

  Various surfactants can be used as the surfactant that can be used in the emulsification dispersion. For example, fatty acid salt, alkyl sulfate ester salt, alkylbenzene sulfonate, alkyl naphthalene sulfonate, dialkyl sulfosuccinate, alkyl phosphate ester salt, naphthalene sulfonate formalin condensate, polyoxyethylene alkyl sulfate ester salt, etc. Surfactant, polyoxyethylene alkyl ether, polyoxyethylene alkyl allyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkylamine, glycerin fatty acid ester, oxyethyleneoxypropylene block Nonionic surfactants such as copolymers are preferred. Further, SURFYNOLS (Air Products & Chemicals), which is an acetylene-based polyoxyethylene oxide surfactant, is also preferably used. An amine oxide type amphoteric surfactant such as N, N-dimethyl-N-alkylamine oxide is also preferred. Further, pages (37) to (38) of JP-A-59-157,636, Research Disclosure No. The surfactants described in 308119 (1989) can also be used.

  In order to stabilize immediately after emulsification, a water-soluble polymer can be added in combination with the surfactant. As the water-soluble polymer, polyvinyl alcohol, polyvinyl pyrrolidone, polyethylene oxide, polyacrylic acid, polyacrylamide or a copolymer thereof is preferably used. It is also preferable to use natural water-soluble polymers such as polysaccharides, casein, and gelatin.

  When the oil-soluble compound, the ultraviolet absorber, the antioxidant, and the fine particles containing a hydrophobic polymer, a high-boiling organic solvent, etc. are dispersed in an aqueous medium by the co-emulsification dispersion method, an aqueous ink is particularly important. Control of particle size. In order to increase color purity and density when an image is formed by inkjet, it is preferable to reduce the average particle diameter of the fine particles. Specifically, the volume average particle diameter of the fine particles is preferably 100 nm or less, and more preferably 80 nm or less and 1 nm or more.

  Further, if the fine particles have coarse particles, printing performance may be deteriorated. For example, when the coarse particles clog the nozzles of the head, and even if the clogs are not clogged, the ink may not be ejected or the ejection may be misaligned. Therefore, it is preferable that the ratio of coarse particles is low, and when an ink is prepared, it is preferable that 10 μm or less particles of 5 μm or more are contained in 1 μl of ink and 1000 particles or less of 1 μm or more. As a method for removing coarse particles, a known centrifugal separation method, microfiltration method, or the like can be used. These separation means may be performed immediately after the emulsification dispersion, or may be performed immediately before filling the ink cartridge after various additives such as a wetting agent and a surfactant are added to the emulsification dispersion. In order to reduce the average particle diameter of the fine particles and reduce the coarse particles, it is effective to use a mechanical emulsifier.

  As the emulsifier, known devices such as a simple stirrer, impeller stirring method, in-line stirring method, mill method such as a colloid mill, and an ultrasonic method can be used, but the use of a high-pressure homogenizer is particularly preferable. The detailed mechanism of the high-pressure homogenizer is described in U.S. Pat. No. 4,533,254, JP-A-6-47264, etc., but as a commercially available apparatus, a gorin homogenizer (APV GAULIN INC.), A microfluidizer (MICROFLUIDEX INC.), An optimizer (Sugino Machine Co., Ltd.), etc. can be used. In recent years, a high-pressure homogenizer having a mechanism for atomizing in an ultrahigh-pressure jet stream as described in US Pat. No. 5,720,551 is particularly effective for emulsification dispersion of the present invention. DeBEE2000 (BEE INTERNIONAL LTD.) Is an example of an emulsifying apparatus using this ultra-high pressure jet stream.

  The pressure during emulsification with a high-pressure emulsifying dispersion device is generally 50 MPa or more, preferably 60 MPa or more, and more preferably 180 MPa or more. For example, it is a particularly preferable method that two or more types of emulsifiers are used in combination by a method such as emulsification with a stirring emulsifier and then passing through a high-pressure homogenizer. Also preferred is a method of once emulsifying and dispersing with these emulsifiers, adding an additive such as a wetting agent or a surfactant, and then passing the high-pressure homogenizer again while filling the cartridge with ink.

  When using a low boiling point organic solvent in addition to the high boiling point organic solvent, it is preferable to remove the low boiling point organic solvent from the viewpoint of stability of the emulsion and safety and hygiene. Various known methods can be used as the method for removing the low-boiling organic solvent depending on the type of the solvent. That is, an evaporation method, a vacuum evaporation method, an ultrafiltration method, and the like. This step of removing the low-boiling organic solvent is preferably performed as soon as possible immediately after emulsification.

  In the fine particle dispersion of the present invention, the amount of the hydrophobic polymer used is the sum of the oil-soluble compound, the ultraviolet absorber, the antioxidant, the hydrophobic polymer, and the high-boiling organic solvent constituting the oil phase. 1 to 70% by mass is preferable, and 2 to 50% by mass is more preferable. In the fine particle dispersion of the present invention, the amount of the high-boiling organic solvent used may be the oil-soluble compound, the ultraviolet absorber, the antioxidant, the hydrophobic polymer, and the high-boiling organic solvent that constitute the oil phase. Is preferably from 25 to 95 mass%, more preferably from 30 to 90 mass%, particularly preferably from 40 to 85 mass%.

  There is no particular limitation on the organic solvent used in addition to the high boiling point organic solvent for the preparation of the fine particle dispersion, and it is based on the solubility of the oil-soluble compound and the ultraviolet absorber, the antioxidant, the hydrophobic polymer, and the like. For example, ketone solvents such as acetone, methyl ethyl ketone and diethyl ketone, alcohol solvents such as methanol, ethanol, 2-propanol, 1-propanol, 1-butanol and tert-butanol, chloroform, chloride Chlorine solvents such as methylene, aromatic solvents such as benzene and toluene, ester solvents such as ethyl acetate, butyl acetate and isopropyl acetate, ether solvents such as diethyl ether, tetrahydrofuran and dioxane, ethylene glycol monomethyl ether, ethylene glycol Dimethyl ether Glycol ether solvents etc., and the like. An organic solvent may be used independently and may use 2 or more types together. Depending on the solubility of the dye or polymer, a mixed solvent with water may be used.

  The amount of the organic solvent used is not particularly limited as long as it does not impair the effects of the present invention, but is preferably 10 to 2000 parts by weight, and 100 to 1000 parts by weight with respect to 100 parts by weight of the hydrophobic polymer. Is more preferable. When the amount of the organic solvent used is less than 10 parts by mass, fine and stable dispersion of fine particles tends to be difficult. When the amount exceeds 2000 parts by mass, solvent removal and concentration for removing the organic solvent are performed. The process becomes indispensable and complicated, and there is a tendency that there is no room for formulation design.

  The organic solvent is preferably removed later in terms of the stability of the fine particles when the solubility of the organic solvent in water is 10% or less, or when the vapor pressure of the organic solvent is higher than water. .

  In addition, it is preferable to remove the used organic solvent after preparing the fine particle dispersion. The removal can be carried out at 10 to 100 under normal pressure to reduced pressure conditions, preferably 40 to 100 under normal pressure conditions or 10 to 50 under reduced pressure conditions.

  The fine particle dispersion of the present invention may contain an additive appropriately selected according to the purpose within a range not impairing the effects of the present invention. Examples of the additive include a dispersion stabilizer. The dispersion stabilizer may be added to either the oil phase or the aqueous phase, but is preferably added after the emulsification dispersion is completed. Examples of the dispersion stabilizer include cation, anion, and nonionic surfactants, water-soluble or water-dispersible low molecular compounds, oligomers, and the like. The addition amount of the dispersion stabilizer is 0 to 100% by mass, preferably 0 to 20% by mass, based on the total of the oil-soluble compound and the ultraviolet absorber, the antioxidant and the hydrophobic polymer.

  In the fine particle dispersion of the present invention, the fine particles are preferably contained in an amount of 1 to 45% by mass, more preferably 2 to 30% by mass. The content can be appropriately adjusted by dilution, evaporation, ultrafiltration or the like.

  Although the fine particle dispersion of the present invention can be used in various fields, it is suitable for water-based ink for writing, water-based printing ink, information recording ink, and the like, and is particularly preferably used for the following ink-jet ink of the present invention. be able to.

(Ink composition)
The ink composition of the present invention contains the fine particle dispersion described above, and further contains other components appropriately selected according to the purpose and necessity. Other components are contained within a range that does not impair the effects of the present invention. For example, drying inhibitors, penetration enhancers, antioxidants, antifungal agents, pH adjusters, surface tension adjusters, antifoaming agents, Well-known additives, such as a viscosity modifier, a dispersion stabilizer, a rust inhibitor, a chelating agent, are mentioned.

  The anti-drying agent is preferably used for the purpose of preventing clogging due to dry operation of the ink-jet ink at an ink ejection port of a nozzle used in the ink-jet recording method.

  The drying inhibitor is preferably a water-soluble organic solvent having a vapor pressure lower than that of water. Specific examples include ethylene glycol, propylene glycol, diethylene glycol, polyethylene glycol, thiodiglycol, dithiodiglycol, 2-methyl-1,3. -Propanediol, 1,2,6-hexanetriol, acetylene glycol derivatives, glycerin, polyhydric alcohols typified by trimethylolpropane, ethylene glycol monomethyl (or ethyl) ether, diethylene glycol monomethyl (or ethyl) ether, tri Lower alkyl ethers of polyhydric alcohols such as ethylene glycol monoethyl (or butyl) ether, 2-pyrrolidone, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-ethylene Heterocycles such as Rumoruhorin, sulfolane, dimethyl sulfoxide, sulfur-containing compounds such as 3-sulfolene, diacetone alcohol, polyfunctional compounds such as diethanolamine, urea derivatives, and the like. Among these, polyhydric alcohols such as glycerin and diethylene glycol are more preferable. These anti-drying agents may be used alone or in combination of two or more. The content of the drying inhibitor in the inkjet ink is preferably 10 to 50% by mass.

The penetration enhancer is preferably used for the purpose of allowing ink jet ink to penetrate better into paper.
Examples of the penetration enhancer include alcohols such as ethanol, isopropanol, butanol, di (tri) ethylene glycol monobutyl ether, 1,2-hexanediol, sodium lauryl sulfate, sodium oleate, and a nonionic surfactant. Is mentioned. The penetration enhancer is contained within a range that does not cause printing bleeding, paper loss (print through), and the like, and usually exhibits a sufficient effect when it is contained in an amount of about 5 to 30% by mass in the ink jet ink.

  The antioxidant is used for the purpose of improving image storage stability. As the antioxidant, for example, various organic and metal complex anti-fading agents can be used. Examples of the organic anti-fading agent include hydroquinones, alkoxyphenols, dialkoxyphenols, phenols, anilines, amines, indanes, chromans, alkoxyanilines, and heterocycles. Examples of the metal complex anti-fading agent include nickel complexes and zinc complexes. No. 17643, No. VII, I to J, ibid. 15162, ibid. No. 18716, page 650, left column, ibid. No. 36544, page 527, ibid. No. 307105, page 872, ibid. The compounds described in the patent cited in No. 15162 and the compounds included in the general formulas and compound examples of representative compounds described in JP-A-62-215272, pages 127 to 137 can be used. .

Examples of the antifungal agent include sodium dehydroacetate, sodium benzoate, sodium pyridinethione-1-oxide, p-hydroxybenzoic acid ethyl ester, 1,2-benzisothiazolin-3-one and salts thereof. These are preferably used in the ink in an amount of 0.02 to 1.00% by mass.
An organic base can be used as the pH adjuster. Examples of the organic base include triethanolamine, diethanolamine, N-methyldiethanolamine, dimethylethanolamine and the like. For the purpose of improving the storage stability of the inkjet ink, the pH adjuster is preferably added so that the inkjet ink has a pH of 6 to 10, and more preferably added to have a pH of 7 to 10. .

  Examples of the surface tension adjusting agent include nonionic, cationic or anionic surfactants. The surfactant used as the surface tension adjusting agent is appropriately selected and used from the viewpoints of the foaming properties and defoaming properties of ink compositions, particularly inkjet inks, the presence or absence of bleeding after printing, and the flying property of ink droplets. As the specific surfactant, various surfactants can be used including those exemplified as the surfactant used for the emulsification dispersion, but it is preferable to use a nonionic surfactant.

The surface tension of the ink composition of the present invention is preferably 25 to 70 mN / m, and more preferably 25 to 60 mN / m. The viscosity of the ink composition of the present invention is preferably 30 mPa · s or less, and more preferably 20 mPa · s or less.
As the antifoaming agent, fluorine-based, silicone-based compounds, chelating agents represented by EDTA, and the like can be used as necessary.

  The ink composition of the present invention can be suitably printed on a known recording material. For example, plain paper, resin-coated paper, inkjet-only paper, film, electrophotographic co-paper, fabric, glass, metal, ceramics, and the like can be given. Although there is no restriction | limiting in particular as said recording material, The inkjet exclusive paper is preferable. Examples of the ink jet dedicated paper include, for example, JP-A-8-169172, JP-A-8-27693, JP-A-2-276670, JP-A-7-276789, JP-A-9-323475, and JP-A-62-2. No. 238783, JP-A-10-153898, JP-A-10-217473, JP-A-10-235995, JP-A-10-337947, JP-A-10-217597, JP-A-10-337947, etc. What is being done is mentioned.

  In the present invention, as the recording material, the following recording paper and recording film are preferably used in addition to the ink-jet dedicated paper. The recording paper and the recording film are formed by laminating a support and an ink receiving layer, and, if necessary, laminating other layers such as a backcoat layer. Each layer including the ink receiving layer may be one layer or two or more layers.

Examples of the support include chemical pulps such as LBKP and NBKP, mechanical pulps such as GP, PGW, RMP, TMP, CTMP, CMP, and CGP, and waste paper pulps such as DIP. Conventionally known pigments, binders, sizing agents, fixing agents, cationic agents, paper strength enhancing agents, and the like may be added to and mixed with the pulp as necessary. The support can be formed using various apparatuses such as a long net paper machine and a circular net paper machine. The support may be a synthetic paper, a plastic film sheet, or the like.
The thickness of the support is about 10 to 25 μm, and the basis weight is preferably 10 to 250 g / m ² .

The support may be directly laminated with the ink-receiving layer and the backcoat layer selected as necessary, or after providing a size press or anchor coat layer with starch, polyvinyl alcohol or the like, An ink receiving layer and the back coat layer may be provided. The support may be flattened by a calendar device such as a machine calendar, a TG calendar, or a soft calendar.
Among the supports, paper and plastic film laminated on both sides with polyolefin (eg, polyethylene, polystyrene, polyethylene terephthalate, polybutene and copolymers thereof) are preferable, and white pigment (eg, titanium oxide, oxidized) is used in the polyolefin. Zinc) or a tinting dye (eg, cobalt blue, ultramarine blue, neodymium oxide) is more preferably added.

The ink receiving layer contains a pigment, an aqueous binder, a mordant, a water resistance agent, a light resistance improver, a surfactant, and other additives.
As the pigment, a white pigment is preferable. Examples of the white pigment include calcium carbonate, kaolin, talc, clay, diatomaceous earth, synthetic amorphous silica, aluminum silicate, magnesium silicate, calcium silicate, aluminum hydroxide, alumina, lithopone, zeolite, barium sulfate, calcium sulfate, Examples thereof include inorganic white pigments such as titanium dioxide, zinc sulfide and zinc carbonate, organic pigments such as styrene pigments, acrylic pigments, urea resins and melamine resins. Among these, porous inorganic pigments are preferable, and synthetic amorphous silica having a large pore area is particularly preferable. As the synthetic amorphous silica, either anhydrous silicic acid obtained by a dry production method or hydrous silicic acid obtained by a wet production method can be used, but hydrous silicic acid is particularly preferred.

  Examples of the aqueous binder include water-soluble polymers such as polyvinyl alcohol, silanol-modified polyvinyl alcohol, starch, cationized starch, casein, gelatin, carboxymethylcellulose, hydroxyethylcellulose, polyvinylpyrrolidone, polyalkylene oxide, and polyalkylene oxide derivatives. And water dispersible polymers such as styrene butadiene latex and acrylic emulsion. These may be used individually by 1 type and may use 2 or more types together. Among these, polyvinyl alcohol and silanol-modified polyvinyl alcohol are preferable in terms of adhesion to the pigment and peel resistance of the ink receiving layer.

  The mordant is preferably immobilized, and a polymer mordant is preferred for that purpose. Examples of the polymer mordant include JP-A Nos. 48-28325, 54-74430, 54-124726, 55-22766, 55-142339, 60-23850, 60-23835, 60-23852, 60-23835, 60-57836, 60-60643, 60-118834, 60-122940, 60-122941, 60-122942, 60 -235134, JP-A-1-161236, U.S. Pat.Nos. 2,484,430, 2,548,564, 3,148,061, 3,309,690, 4,115,124, 4,124,386, 4,193,800, 4,427,533, 4,282,305 Are described in each specification of US Pat. No. 4,450,224. A polymer mordant described on pages 212 to 215 of JP-A-1-161236 is preferable. Use of these polymer mordants is preferred in that an image with excellent image quality can be obtained and the light resistance of the image is improved.

  The water-proofing agent is used for the purpose of making the image water-resistant. As the water-proofing agent, a cationic resin is preferable. Examples of the cationic resin include polyamide polyamine epichlorohydrin, polyethyleneimine, polyamine sulfone, dimethyldiallylammonium chloride polymer, and cationic polyacrylamide. Among these cationic resins, polyamide polyamine epichlorohydrin is particularly preferable. The content of the cationic resin is preferably 1 to 15% by mass, and more preferably 3 to 10% by mass with respect to the total solid content of the ink receiving layer.

  Examples of the light resistance improver include zinc sulfate, zinc oxide, hindered amine-based antioxidants, benzophenone-based and benzotriazole-based ultraviolet absorbers, and the like. Among these, zinc sulfate is particularly preferable.

  The surfactant functions as a coating aid, a peelability improver, a slippage improver or an antistatic agent. Examples of the surfactant include those described in JP-A Nos. 62-173463 and 62-183457. An organic fluoro compound may be used instead of the surfactant. The organic fluoro compound is preferably hydrophobic. Examples of the organic fluoro compounds include fluorine surfactants, oily fluorine compounds (eg, fluorine oil) and solid fluorine compound resins (eg, tetrafluoroethylene resin). No. (columns 8 to 17), JP-A Nos. 61-20994 and 62-135826, and the like.

Examples of the other additives include pigment dispersants, thickeners, antifoaming agents, dyes, fluorescent whitening agents, preservatives, pH adjusters, matting agents, hardeners, and the like.
The back coat layer contains a white pigment, an aqueous binder, and other components.

  Examples of the white pigment include light calcium carbonate, heavy calcium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, calcium silicate. , Magnesium silicate, synthetic amorphous silica, colloidal silica, colloidal alumina, pseudoboehmite, aluminum hydroxide, alumina, lithopone, zeolite, hydrous halloysite, magnesium carbonate, magnesium hydroxide, white inorganic pigments, styrene plastic pigment, acrylic And organic pigments such as plastic pigments, polyethylene, microcapsules, urea resins, and melamine resins.

Examples of the aqueous binder include styrene / maleate copolymer, styrene / acrylate copolymer, polyvinyl alcohol, silanol-modified polyvinyl alcohol, starch, cationized starch, casein, gelatin, carboxymethylcellulose, hydroxyethylcellulose, and polyvinylpyrrolidone. And water dispersible polymers such as styrene butadiene latex and acrylic emulsion.
Examples of the other components include an antifoaming agent, an antifoaming agent, a dye, a fluorescent brightening agent, a preservative, and a water resistant agent.

  A polymer latex may be added to each layer in the recording paper and recording film. The polymer latex is used for the purpose of improving film physical properties such as dimensional stabilization, curling prevention, adhesion prevention, and film cracking prevention. Examples of the polymer latex include those described in JP-A Nos. 62-245258, 62-136648, and 62-110066. When a polymer latex having a low glass transition temperature (40 ° C. or lower) is added to the layer containing the mordant, cracking and curling of the layer can be prevented. Further, curling can be prevented by adding a polymer latex having a high glass transition temperature to the back coat layer.

  The ink composition of the present invention can be used in various fields, but is suitable for a water-based ink for writing, a water-based printing ink, an information recording ink, and the like, and is particularly preferably used as an ink used in an ink jet recording system. be able to.

  The ink composition of the present invention can be applied to any ink jet recording system. For example, a charge control system that ejects ink using electrostatic attraction, a drop-on-demand system (pressure pulse that uses vibration pressure of a piezoelectric element) Method), acoustic ink jet method that changes the electrical signal into an acoustic beam, irradiates the ink and ejects the ink using the radiation pressure, thermal ink jet (bubble jet) that heats the ink to form bubbles and uses the generated pressure (Registered trademark)) system, etc. The ink jet recording method includes a method of ejecting a large number of low-density inks called photo inks in a small volume, a method of improving the image quality using a plurality of inks having substantially the same hue and different concentrations, and a colorless and transparent type. A method using ink is included.

  Examples of the present invention will be described below, but the present invention is not limited to these examples. In this example, “parts” and “%” represent “parts by mass” and “% by mass” unless otherwise specified.

(Preparation of fine particle dispersion (A-1))
16 parts of ethyl acetate, 2.7 parts of hydrophobic polymer (PA-1) (solid content 50%), 0.45 parts of the following oil-soluble dye (M-1, oxidation potential 1.39 eV), and ultraviolet absorber ( Exemplified UV-2) A mixed solution of 0.1 part was prepared. On the other hand, a mixed liquid of 18 parts of water and 0.4 part of “Emar 20C” (Kao Corporation) was prepared. After combining the above two types of liquid mixture, the mixture was emulsified and dispersed with a homogenizer (manufactured by Nippon Seiki Co., Ltd.), then concentrated under reduced pressure at a temperature of 30 ° C. to remove ethyl acetate, and a solid content of 17% A fine particle dispersion was prepared. The volume average particle size of the fine particles in this fine particle dispersion was 78 nm as measured with “LB-500” manufactured by HORIBA. Hereinafter, this is abbreviated as a fine particle dispersion (A-1).

(Preparation of fine particle dispersion (A-2))
16 parts of ethyl acetate, 2.7 parts of hydrophobic polymer (PA-1) (solid content 50%), 0.45 part of the following oil-soluble dye (M-1), and an ultraviolet absorber (the above-mentioned exemplified UV-3) ) 0.1 part of a mixed solution was prepared. On the other hand, a mixed solution of 18 parts of water and 0.4 part of Emar 20C (Kao Corporation) was prepared. The two mixed liquids were combined and then stirred and mixed with a magnetic stirrer to prepare an oil-in-water type coarse particle dispersion. Next, the coarse particle dispersion was passed through an optimizer (manufactured by Sugino Machine Co., Ltd.) at a pressure of 345 mPa for 5 times to make fine particles. The resulting emulsion was concentrated under reduced pressure at a temperature of 30 ° C. to remove ethyl acetate, and a fine particle dispersion having a solid content of 17% was prepared. The volume average particle size of the fine particles in this fine particle dispersion was 25 nm as measured with “LB-500” manufactured by HORIBA. Hereinafter, this is abbreviated as a fine particle dispersion (A-2).

(Preparation of fine particle dispersion (A-3))
16 parts of ethyl acetate, 2.7 parts of hydrophobic polymer (PA-1) (solid content 50%), 0.45 part of the following oil-soluble dye (M-1), and ultraviolet absorber (the above-mentioned exemplified UV-12) ) 0.1 part of a mixed solution was prepared. On the other hand, a mixed solution of 18 parts of water and 0.4 part of Emar 20C (Kao Corporation) was prepared. The two mixed liquids were combined and then stirred and mixed with a magnetic stirrer to prepare an oil-in-water type coarse particle dispersion. Next, this coarse particle dispersion was micronized by passing it through a microfluidizer (MICROFLUIDEX INC) five times at a pressure of 600 bar. The resulting emulsion was concentrated under reduced pressure at a temperature of 30 ° C. to remove ethyl acetate, and a fine particle dispersion having a solid content of 17% was prepared. The volume average particle diameter of the fine particles in this fine particle dispersion was 40 nm as measured with “LB-500” manufactured by HORIBA. Hereinafter, this is abbreviated as a fine particle dispersion (A-3).

(Preparation of fine particle dispersion (A-4))
16 parts of ethyl acetate, 2.7 parts of hydrophobic polymer (PA-13) (solid content 50%), 0.45 part of the following oil-soluble dye (M-1), and an ultraviolet absorber (the above-mentioned exemplified UV-13) ) 0.1 part of a mixed solution was prepared. On the other hand, a mixed solution of 18 parts of water and 0.4 part of Emar 20C (Kao Corporation) was prepared. After combining the above two types of liquid mixture, the mixture was emulsified and dispersed with a homogenizer (manufactured by Nippon Seiki Co., Ltd.), then concentrated under reduced pressure at a temperature of 30 ° C. to remove ethyl acetate, and a solid content of 17% A fine particle dispersion was prepared. The volume average particle size of the fine particles in the fine particle dispersion was measured with “LB-500” manufactured by HORIBA, Inc., and found to be 85 nm. Hereinafter, this is abbreviated as a fine particle dispersion (A-4).

(Preparation of fine particle dispersion (A-5))
16 parts of ethyl acetate, 2.7 parts of hydrophobic polymer (PA-13) (solid content 50%), 0.45 part of the following oil-soluble dye (M-1), and an ultraviolet absorber (the above-mentioned exemplified UV-14) ) 0.1 part of a mixed solution was prepared. On the other hand, a mixed solution of 18 parts of water and 0.4 part of Emar 20C (Kao Corporation) was prepared. The two mixed liquids were combined and then stirred and mixed with a magnetic stirrer to prepare an oil-in-water type coarse particle dispersion. Next, the coarse particle dispersion was passed through an optimizer (manufactured by Sugino Machine Co., Ltd.) at a pressure of 345 mPa for 5 times to make fine particles. The resulting emulsion was concentrated under reduced pressure at a temperature of 30 ° C., and ethyl acetate was removed to prepare a fine particle dispersion having a solid content of 17%. The volume average particle size of the fine particles in this fine particle dispersion was 30 nm when measured with “LB-500” manufactured by HORIBA. Hereinafter, this is abbreviated as a fine particle dispersion (A-5).

(Preparation of fine particle dispersion (A-6))
16 parts of ethyl acetate, 2.7 parts of hydrophobic polymer (PA-1) (solid content 50%), 0.45 parts of the oil-soluble dye (M-1), and antioxidant (triethylene glycol-bis ( 3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate) 0.1 parts of a mixture was prepared, while water 18 parts and Emar 20C (Kao Corporation) 0.4 parts After mixing the above two types of mixture, the mixture was emulsified and dispersed with a homogenizer (manufactured by Nippon Seiki Co., Ltd.), and concentrated under reduced pressure at a temperature of 30 ° C. to remove ethyl acetate. A fine particle dispersion having a solid content of 17% was prepared, and the volume average particle size of the fine particles in this fine particle dispersion was 85 nm as measured by “LB-500” manufactured by HORIBA Co., Ltd. This is a fine particle dispersion (A 6) and abbreviated.

  Table 1 shows the respective components and particle sizes of the fine particle dispersions A-1 to A-6.

  As is clear from the results in Table 1 above, a fine particle dispersion having no aggregation and a small particle size was obtained.

[Example 1]
(Preparation of ink composition 01)
The following components were mixed and filtered through a 0.45 μm filter to prepare an aqueous ink composition 01 for inkjet recording.
・ Particulate dispersion (A-1) 50 parts ・ Diethylene glycol 5 parts ・ Glycerin 18 parts ・ Triethanolamine 1 part ・ Orphine E1010 1 part ・ Water Total amount of 100 parts

[Example 2]
(Preparation of ink composition 02)
The following components were mixed and filtered through a 0.45 μm filter to prepare an aqueous ink composition 02 for inkjet recording.
・ Particulate dispersion (A-2) 50 parts ・ Diethylene glycol 5 parts ・ Glycerin 10 parts ・ 1,2-Hexanediol 8 parts ・ Triethanolamine 1 part ・ Orphine E1010 1 part ・ Water 100 parts in total

[Examples 3 to 6]
(Preparation of ink compositions 03 to 06)
In Example 1, an aqueous solution was used in the same manner as in Example 6 except that the fine particle dispersion (A-3 to A-6) prepared as described above was used instead of the fine particle dispersion (A-1). Inkjet recording ink compositions (03 to 06) were prepared.

[Comparative Example 1]
(Preparation of ink composition 07)
A mixed solution of 16 parts of ethyl acetate, 2.7 parts of hydrophobic polymer (PA-1) (solid content 50%), and 0.5 part of an ultraviolet absorber (UV-2) was prepared. On the other hand, a mixed solution of 18 parts of water and 0.4 part of “Emar 20C” (Kao Corporation) was prepared. After combining the above two types of liquid mixture, the mixture was emulsified and dispersed with a homogenizer (manufactured by Nippon Seiki Co., Ltd.), then concentrated under reduced pressure at a temperature of 30 ° C. to remove ethyl acetate, and a solid content of 17% An ultraviolet fine particle dispersion was prepared.
Next, the following materials were mixed and filtered through a 0.45 μm filter to prepare an aqueous ink jet recording ink composition (07) of Comparative Example 1.
-4 parts of the following water-soluble dye (DD-1, oxidation potential 0.61 eV)-0.8 part of the above UV absorber dispersion-8 parts of diethylene glycol-7 parts of triethylene glycol monobutyl ether-10 parts of glycerin-triethanolamine 1 Part ・ Olfin E1010 1 part ・ Amount of 100 parts in total

[Comparative Example 2]
(Ink composition 08)
Ink for printer “PX-G900 magenta ink (pigment ink)” manufactured by Epson Corporation was used as the ink composition 08 of Comparative Example 2.

(Image recording and evaluation)
Each ink composition (01-08) prepared above is filled into a cartridge of an inkjet printer “MC-2000” manufactured by EPSON Corporation, and using this machine, plain paper for PPC and inkjet paper “photo glossy paper” are used. Images were recorded on “EX” (manufactured by Fuji Photo Film Co., Ltd.) and evaluated as follows. The evaluation results are shown in Table 2 below.

(1) Evaluation of printing performance After setting the cartridge in the printer and confirming the ejection of ink from all the nozzles, an image was output on 10 sheets of A4 paper, and the printing disturbance was evaluated according to the following criteria.
A: There was no disorder in printing from the start to the end of printing.
B: Disturbance of printing occasionally occurred from the start to the end of printing.
C: The printing was disturbed from the start to the end of printing.

(2) Evaluation of paper dependency The color tone of the image formed on the photo glossy paper and the image formed on the PPC plain paper is compared, and when there is almost no difference between the two images, the difference between the two images is small. The case was evaluated as B, and the case where the difference between the two images was large as C.
(3) Gloss Evaluation The gloss unevenness of the sample printed on the photo glossy paper is visually evaluated. A sample having no gloss unevenness is B, a slight unevenness is B, and a gloss unevenness is clearly identified as C. A three-stage evaluation was performed. This uneven gloss becomes prominent when the ink for ink jet recording is not sufficiently soaked in the recording paper, and serves as an index of the soaking property.

(4) Evaluation of water resistance The photo glossy paper on which the above image was formed was dried at room temperature for 1 hour, then immersed in water for 30 seconds, naturally dried at room temperature, and bleeding was observed. Evaluation was made in three stages, with A indicating no bleeding, B indicating slight bleeding, and C indicating excessive bleeding.
(5) Light resistance evaluation The photo glossy paper on which the image is formed is irradiated with xenon light (100,000 lx) for 7 days using a weather meter “Atlas C.I65”, and the image density before and after the xenon irradiation is measured by a reflection densitometer. It measured using "X-Rite310TR" and evaluated as a pigment residual rate (%). Here, the reflection density was measured at three points of 1, 1.5, and 2.0. At any concentration, the evaluation was made in three stages, with A being a dye residual ratio of 80% or more, B being less than 80%, and C being less than 70%.

(6) Ozone resistance For ozone resistance, the optical density before and after storing the sample for 7 days under the condition of ozone concentration of 0.5 ppm was measured with “X-rite 310”, and the residual ratio of colorant (% ) Was evaluated. When the dye residual ratio was 90% or more, A, 89-80% B, 79-70% C, 69-50% D, and less than 49% E were evaluated in 5 stages.

(7) Image recording and evaluation The ink prepared above was evaluated. The dryness evaluation, fine line bleeding evaluation, and scratch resistance evaluation were evaluated by the following methods.
(Dryness evaluation)
Immediately after printing the image, the image area was touched with a finger, and the resulting stain was visually evaluated.
(Evaluation of fine line bleeding)
A fine line pattern was printed and visually evaluated.
(Abrasion resistance evaluation)
After the image was printed, an image that was aged for 30 minutes was rubbed with an eraser and visually evaluated for the presence or absence of a density change in the image area.

  As is apparent from the results in Table 2 above, the ink composition of the present invention has good printability on various recording media, excellent light resistance and ozone resistance, gloss, excellent water resistance and bleeding. It was.

Claims (7)

  Containing a fine particle dispersion in which fine particles containing an oil-soluble compound having an oxidation potential nobler than 1.0 V (vs SCE) and an ultraviolet absorber and / or an antioxidant are contained in an aqueous medium. An ink composition.   The ink composition according to claim 1, wherein the oil-soluble compound is an oil-soluble dye.   The ink composition according to claim 1, wherein the fine particle dispersion further contains a hydrophobic polymer.   4. The ink composition according to claim 1, wherein a long wave end of an absorption wavelength of the ultraviolet absorber is 410 nm or less. 5.   The ultraviolet absorber is at least one selected from the group consisting of benzophenones, benzotriazoles, oxalic anilides, cyanoacrylates, and triazines. 2. The ink composition according to item 1.   The ink according to any one of claims 1 to 5, wherein the antioxidant is at least one selected from the group consisting of phenols, phosphites, hindered amines, and thioethers. Composition.   The ink composition according to claim 1, wherein the ink composition is for inkjet recording.